How to Build, Buy, and Sell Apps Like LetGo or OfferUp?

All these reasons to buy and sell goods make apps like OfferUp a good business idea. You can create your own e-space for people to sell their unnecessary belongings and buy something they want. We have developed a guide to the world of sites like OfferUp for you. We will start our journey with a market overview, then dive into the functionality of buy-and-sell apps and look through a plan with precise cost to develop such an app.

How do buy-and-sell apps work?

The working mechanics of apps like LetGo and OfferUp are simple:

• • a user registers and fills in basic personal information,
  • a seller lists their goods to sell: adds pictures, descriptions, and prices,
  • customers search for goods they want,
  • if needed, a customer can connect with a seller via chat and discuss the specifics of a good,
  • a customer buys goods they chose or barters with a seller.

This kind of app is an electronic version of a market: people have an opportunity to buy and sell goods among each other without companies ruling the market.

Buy-and-sell apps market overview

E-commerce is a fast-growing market: eMarketer report shows a 16.8% increase in buying and selling online all over the world. Moreover, the global e-commerce market was expected to surpass $6 trillion in 2024, with 21% of all sales made online. That’s a lot!

Peer-to-peer marketplaces are also a promising sector. As stated by Future Market Insights, this e-commerce segment is estimated to be valued at US$ 1,526.2 million in 2024 and, more than that, is expected to grow fivefold by the year 2032. A cumulative annual growth rate of 15.5% makes it an attractive opportunity to develop an app like OfferUp or LetGo. However, there are several confident competitors to consider before the start.

Apps like OfferUp and LetGo: differences matter

There are several buy-and-sell apps on the market. They all have the same basic functionality, however differ in details. Let us dive into each of them for a better understanding of the apps like OfferUp.

OfferUp

OfferUp is the biggest marketplace app for local users. It works in the USA, excluding Hawaii, Alaska, and Arkansas. Developers of the app pay great attention to security with safe deals and authorization services. Also, both customers and sellers can rate each other and provide deal feedback.

A hallmark of the app is the creation of digital communities. That is the key to its popularity: users spend an average of 25 minutes per day on the app, the same as Instagram or Snapchat.

LetGo

In 2020, LetGo became a part of OfferUp. It has some strong features you should consider to develop in your own app. First, sign up with a Facebook account — it makes the registration process easier and helps verify user data for security. Second, location-based advertising of goods. Sellers can place ads and broaden the audience without extra spending.

However, the app has a huge limitation as there is no built-in payment system, the users should define the payment terms on their own. Not only is it inconvenient, but also unsafe for both parties.

eBay

Although it’s a US-based marketplace app, eBay is well-known across the globe for almost worldwide delivery. It is a huge competitor of all local buy-and-sell apps since you can look for the product in a particular region with a zip-code filter. eBay has a vast variety of goods categories, PayPal integration, and a simple interface, however, it lacks round-the-clock customer support.

Craigslist

This marketplace app works in 70 countries and serves 55 million users. The number of product categories is also huge and includes real estate and vacancies, which is a rare feature for a buy-and-sell app. It has secure transactions as the main competitive advantage. Craigslist positions itself as a fee-free app, however, listing in some categories will cost you $3-4.

VarageSale

As stated by the name, this is an app for online garage sales. Users can search for goods only in a small geographical area, which creates the atmosphere of the neighborhood. The security is supported by registration with real Facebook accounts. The app has a killer feature: all goods are manually inspected to protect users from scams and fraud.

Listia

A unique feature of Listia is an internal credit system — users pay for the goods with Listia credits instead of real money. There is an alternative way to earn credits: users can list items, give goods away, invite friends into the app, or sign in with social media accounts.

How do apps like OfferUp make money?

Person-to-person marketplace apps have a similar business model. Ordinarily, these apps are free for download and registration. However, they can take a fee for several in-app actions or make a profit through their audience coverage, for example by showing ads to users. For your buy-and-sell app, you can choose from this list of app monetization strategies.

Internal Ads

You can offer in-app ads for sellers in order to promote their goods and make deals faster in apps like OfferUp. It works efficiently with an internal recommendation system and the ability to create special offers and discounts.

Member Fee

This type of monetization strategy creates two ways of business:

• • you can provide some special functions on a commercial basis. For example, placing the ads on top of all search results or showing ads during calls;
  • or you can create common fee or subscription plans. For example, we created 3 subscription plans for Contentplace, a video content marketplace.

Seller Fee

Some of the buy-and-sell apps charge a commission from the seller for listing. Generally, the fee is between 1 and 5% of the price. However, you can create your own scale for the commission and, for example, charge small traders less. Please note that this business model will work if your app provides significant value for sellers and makes their interaction with customers easier.

Transaction Fee

A fee for a transaction is the most common way to profit from an app. You can include a commission (fixed cost or a percentage) for a buyer in every deal made through your service, just like OfferUp.

External Ads

When your app audience is huge enough, you can make the app free for users and generate profit from external advertisers. You can attract companies to include their banners in your app interface. Use your resources for external communication or delegate them to an advertising agency.

Basic features of apps like OfferUp

Your future buy-and-sell app should include these must-have features:

• • signup through email and social media,
  • cart, 
  • built-in payment system,
  • camera,
  • chat for buyers and sellers,
  • technical support,
  • push notifications.

However, it is not enough for a pleasant customer experience. To build an app like LetGo or OfferUp, one should develop a product card with all the necessary fields. The best practice is to include:

• • photos,
  • description,
  • price,
  • place of the deal,
  • delivery options,
  • and whether the goods are new or used.

Experts also recommend including an advanced search engine in a buy-and-sell app with lots of categories, subcategories, and comprehensive filters. This will help improve user experience as potential buyers can find just the item they want in terms of color, size, type, brand, etc.

We have created a marketplace app for home rentals with plenty of tags. Learn more about it as an inspiration for filter creation.

You should also consider rating and feedback mechanisms because they motivate users to be fair in their deals. Especially since the feedback is a two-way street.

Extra features of marketplace apps

Additional functionality can create a unique customer experience and brand ambassadors for your app.

1. Sophisticated recommendation systems

Search with photo scanning and price comparison can speed up the search of the goods. Also, you can offer hot deals based on favorite goods and previous purchases in your app.

2. Virtual try-on

You can also enhance the user experience by adding virtual try-on in your buy-and-sell app. It is an almost obligatory feature for beauty and clothing marketplaces as it helps select goods that suit perfectly to the buyers’ needs.

3. Integrations

Some people would appreciate built-in delivery or integration with post services as it is more convenient to push one or two buttons in an app instead of going to a post office and arranging the delivery. By the way, it is one more way to monetize your app, like OfferUp or LetGo, and raise your profit.

4. Safety

App security is one more way to improve your service. Either manual or automatic, fraud protection will help build trust with your users and can be a decisive factor when a person chooses a buy-and-sell app for themselves.

4 steps to create a buy-and-sell app

The creation of a marketplace app has the same structure as any other mobile app development. However, there are several details to consider at every step for apps like OfferUp.

1. Market research

Learn how other apps like LetGo or OfferUp built their business model and what kind of features they have. Try to get the experience of both buyers and sellers. Put attention to inconvenient interfaces or illogical menus — all these mistakes should be avoided in a buy-an-sell app.

2. Finding a developer agency

If you don’t have a team of professional developers, you may choose a development company for your future app building. Start your search from the companies’ portfolio: an agency should have a number of relevant cases. Put attention to clients’ references and reviews as a clear indicator of the company’s approach to relations with customers.

3. Building an MVP

MVP (minimum viable product) is a comprehensive prototype of your future buy-and-sell app with all features in its basic performance. The creation of MVP helps you test the water early, and minimize cost to develop, as well as collect feedback from real users for future marketplace app development.

The agency you’ve chosen will help you with development.

4. Release and Maintenance

After a buy-and-sell app’s release starts a huge phase of maintenance and development. The more users use the app, the more feedback you will get. This way, you’ll learn how your app satisfies the users’ needs. And that is a great opportunity to connect with your users and create a better app for them. Do not hesitate to engage the development team — they know your app better than anybody and will help you further improve the functionality and design.

How much will it cost to develop a local marketplace app?

We prepared a rough guideline on the time and money needed for mobile app development. There are four key stages:

Project Estimation

You and your development agency will discuss the app idea and estimate the time and costs for development. This stage is normally free of charge.

UI and UX design

The design includes not only the visual representation but also the key functions of your app. In this stage, we plan everything you want to see in your future marketplace app, from sign-in to delivery.

To develop a design for a buy-and-sell app, you need:

⏰ 130 hours
💰 $7,000

Development

We use React Native. It saves time and money since we develop both iOS and Android apps in parallel. This is the most time-consuming stage. The team develops the architecture and the interface on both the client and server sides.

⏰ 900 hours

💰 $44,500

Here is what you get for your buck feature-by-feature:

Features	Time for development, hours	Cost of development, $
Social sign-in	60	3,000
Product card	60	3,000
Cart	80	4,000
Search engine	60	3,000
Payment system	40	2,000
Chat	300	15,000
Notifications	24	1,200
Goods filters	40	2,000
Rating and feedback mechanism	40	2,000

QA Testing

Testing is important. Аll the bugs should be identified and cleaned up before the launch. Our QA engineers will work it up for you.

⏰ 300 hours
💰 $7,500

There is one more additional spending item — project management. A professional manager assigns tasks and controls deadlines and costs of development.

💰 $5,000

The total spending for an app development is $67,700.

Summary: takeaways and the first steps

For your convenience, here is a recap of essential statements:

• • all current apps in the market have quite a similar functionality with email and social media registration, goods description, e-commerce tools, notifications, chat, built-in camera, support, rating, and feedback;
  • there are 4 steps to build an app like LetGo or OfferUp:
    1) market analysis,
    2) development of an MVP,
    3) release,
    4) maintenance.
  • total expenses for a marketplace app are around $67,700.

Even before local market analysis, you can make a first step for your future app creation. It can be a free consultation with a Purrweb specialist on how to develop an app like LetGo or OfferUp. We can discuss your expectations and time frame for mobile app development. Moreover, we will give you some recommendations based on our experience in app creation for your market and industry. Contact us or fill out the form.