Okay so the game tells you that foods with the save icon can be saved.
That's a lie, some foods without that icon can be saved too.

Despite not having the save icon; partially cooked doners can be saved. Left-over cooked meat cannot and you cannot pick doners with cooked sides. At the end of the day remove any leftover cooked meat from the doner and put it in the freezer.

Kebabs have a sort of grace period when placed on the grill.
That means that you have around 2/3 seconds to pick them back up and have them return to their wholly uncooked form. This is very useful if you mistakenly put the wrong kebab on the grill

Lettuce, tomatos, pickles do not require cooking and therefore will only be removed if they aren't in a freezer at the end of the day.

This section will outline what upgrades you should get first.

Max this first
The "Bonus Tip" upgrade on the cashier is free money and they easily repay their salary cost within two tips or less. If you still want to accept orders by hand that's fine as long as you have them working with that upgrade.

This is conjecture but...
I'm convinced that buying more space attracts more customers.
However, this might be wrong I have yet to test this to be honest.
Simply put, by the time you buy more space, more customers might've simply started coming because of how far you're in the game.

Getting this to level 3 is a pain in the ass but the bonus cash is worth it especially when you unlock beef doners, plus other stations aside from the grill are kinda meh.

How much of X do you need per day.

I suggest that after unlocking fries you cook two batches of them on the same oil per day.
After the 2nd batch is done, simply remove the basket from the machine and put it on the counter top and use it to refill the station when needed.
They are both used in wraps and as a side so you'll be going through them fast.

You can use the paper things to interact with a station to fill them instead of putting the fries into said container like an absolute bafoon. Prepared fry side can be inserted into one of 5 slots available on the fry station.

Lettuce
Around 6-8 per day. Just refill after the last customers go away.

Tomatos
Those are used more commonly than lettuce, around 8-12 per day

Pickles
8-10 per day

Doners
You'll probably need more than 4 but no more than 8 for both chicken and beef

Kebabs
Those bastards run out fast. Depending on the day it's between 6/8
I strongly advise always keeping at least one additional box of each type / buying a box a day.

You'll have to rarely restock on those. Probably once every 8 days or so.

You might have noticed that this game is made by a small studio.
This means there's little server side validation and security.

If you're curious about memory hacking and some tomfoolery read the following.
Do note that I was just messing around and found all of this under an hour so it's not extensive. Yo can probably teleport people out of bounds in this game and do some nasty ♥♥♥♥.

1. No Credit Score
As one can see at the checkout page our money is stored in a format that supports (.)
That usually is a float. By searching for this value in memory we're left with... nothing.
That's because devs sometimes opt to use "doubles". This yields around 8 memory adresses.

Now, if you're the client this still works. How?
Go to the PC, enter it, change the balance to some random positive number and go buy stuff.
At the check out you will notice that the game thinks you have that money you just cheated in.
Well after you buy the stuff you can go over the negative amount. That means you have infinite money or rather infinit debt.

Why does this work? Well I'd assume the server doesn't check the actual balance when you buy the stuff but simply reduces the amount of money you have by the cost. Issue is you really don't have that money so you go into further debt

This also works for upgrades and black jack btw.

2. Luckiest Gambler
This is a simple exact value scan for the amount of point you hold. It's a single memory address.
When you find it, change it to 21 and freeze it. It will persist through blackjack sessions that way aswell as removing yourself from the monitor. The game will add points to your 21 score but it doesn't matter. You will win each time.

3. Unlimited Stakes
Enter a blackjack game for $200, scan for addresses, then $100 etc. You'll be left with 2 addresses.
Change the address value to whatever amount of money you want to.

Now if you ran the Luckiest Gambler you have 100% of winning that money and potentially reversing your debt.

You probably also increase the amount of money received from picking it up