To me the approach you are taking seems very difficult to understand and manage. Maybe someone else will have better luck understanding what you are trying to do and what your next step would be.
If you are willing to do some rework of your project, here is a link to a project that does some of what you want. The store starts out in a closed state and after a certain number of ticks, goes to an open state. When open it is possible to make sales of a random quantity of random products to up to a maximum number of customers by clicking a button.store.capx
To upgrade the number of customers you would just change MaxCustomers.
Do you mean increase the profit or increase the revenue? If you mean revenue (which is price * qty) then just multiply by another upgrade factor and make it price*qty*factor. For example, 3*10=30 vs 3*10*1.5=45.
If you have questions about the capx I linked to, let me know.kittiewan2012-04-02 22:07:19