I've helped a bunch of first-time retail and cafe owners set up their iPad POS, and the same 3 mistakes keep showing up:

1. Buying hardware before picking software.

People buy a stand, a card reader, and a printer — then find out their POS app doesn't support half of it. Pick your software first. It dictates every hardware decision after.

2. Ignoring processing fees until the first statement.

A lot of POS apps advertise a low monthly fee but bury a much higher card processing rate. Always ask for the all-in rate before you sign up, not after your first month of sales.

3. Skipping the offline mode test.

Your Wi-Fi will go down during a Saturday rush eventually. If you haven't tested your POS in offline mode before that happens, you'll be turning away paying customers at the worst possible time.

Setting this up right the first time saves you weeks of headaches and switching costs later. If you're mid-setup and stuck, happy to help in the comments.