How do I handle haggled prices across a bundle of items?

Record the price actually paid and split it across the items in proportion to their asking prices. That keeps per-household totals fair when a buyer takes a lamp from one family and a chair from another for one round number, and it avoids the end-of-day argument the app exists to prevent.

Should the app take card payments?

Not in version one. Most sales are cash or a payment app the seller already uses. Record the payment method so the cash box reconciles, and skip payment processing until there is a clear reason — like estate sale companies running large sales every week.

How to Build a Garage Sale App with AI (2026)

What a garage sale app needs

Add items with a photo, asking price, and which household owns them
Record a sale with the actual price paid, even when it was haggled
Running total of takings by household and by payment method
Remaining items list to decide what gets donated
Share an item list with photos before the sale to attract buyers

The screens

Screen	What it does
Items	Grid of items with photo, asking price, and sold or unsold
Add Item	Photo, title, asking price, household, category
Sell	Pick one or more items, enter price paid and payment method
Takings	Totals by household and payment method, sold versus unsold
Share	A public list of items and prices to post before the sale

The data model

Sale: name, date, address, startTime, endTime
Household: saleId, name, colour
Item: saleId, householdId, title, photoUri, category, askingPrice, status
Transaction: saleId, paidAt, total, paymentMethod
TransactionLine: transactionId, itemId, pricePaid

The build prompt (copy this)

Paste this into ShipNative and it becomes a working React Native app with these screens, navigable in a live preview, in about two minutes:

“A garage sale helper for one sale day, with support for several households selling together. Items is a photo grid of everything for sale with the asking price and a sold badge, filterable by household and category. Add Item is optimized for pricing forty things in one evening: take a photo, type a short title and a price, pick the household from coloured chips, save and immediately start the next item. Sell is used on the day with a buyer waiting: tap one or more items, the asking total appears, and the seller can overwrite it with the price actually agreed — split across the items proportionally — then pick cash or a payment app. Takings shows running totals per household and per payment method so the cash box can be reconciled at the end, and a list of unsold items to donate or keep. Share generates a simple public page with photos and prices so the sale can be posted to neighbourhood groups the day before. No accounts needed for one household; invite a second phone with a code when households sell together so both can record sales. Works offline. Screens: Items, Add Item, Sell, Takings, Share.”

Then iterate with small, screen-specific prompts (“make the primary button bigger”, “add an empty state”), preview on your own phone, and export the full Expo project whenever you want. The full method: how to build an app with AI.

How it makes money

Honestly thin as a standalone business — people hold a garage sale once or twice a year. It works as a free app with a small one-time unlock for multi-household sales, or as a lead-in to something bigger: a local listings app, a moving checklist, or a tool for estate sale companies, who run sales every weekend and will pay.

Implementation and the revenue math for every model: how to make money from an app. When you’re ready to ship: App Store and Google Play publishing guides.

Build it now

The prompt above is free to run at shipnative.dev — working garage sale app on your phone today, full code export, no credit card.

How to Build a Garage Sale App with AI