A second shop is not twice the first shop. It is a different business, because the thing that made the first one work, you standing in it, no longer scales.
Prices cannot live in your head any more
In one shop, the owner is the price list. In two, the second counter is guessing, and guesses go in the customer's favour.
Every item needs a rate the system knows, before the second shop opens rather than after.
Each branch needs its own stock
One combined stock figure is worse than useless across two locations: it tells you that you have twelve, and not that all twelve are in the wrong shop.
Stock has to be held per branch, and moving it between them has to be a recorded transfer rather than somebody putting boxes in a car.
- Stock per branch, not one pooled number
- Transfers recorded on both sides
- One login that shows all branches
Cash needs a closing figure
When you are in the shop, you know what the till should hold. When you are not, the only thing standing between you and a slow leak is a daily closing figure that somebody signs off.
That is a habit as much as a feature. Set it from the first week, because introducing it later looks like an accusation.
Reports become the only visibility you have
You will not be in both shops. What today's sales, today's discounts and today's cash were, per branch, on your phone, is the whole of your management from now on.
Shops that open a second branch without this usually discover the problem three or four months in, by which time it is a large number.
Get the first shop running on records rather than on your presence, then open the second. Doing it the other way round is how one good shop becomes two struggling ones.