I'm configuring Zoho CRM, but the products module doesn't fit my business requirements.

I want to be able to associate to each client a loan/pawn system. So, for the "products" module, the price is variable depending on the amount on cash the client demands. It's possible to do something like this? 

Also, Zoho Suscriptions integration sounds good for charging them monthly, but the clients is who sets the day of charge (it can be different from month to month) and also the amount that he wants to pay for taking away some part of the loaned quantity.

Is any way at Zoho for achieving this?

TIA, cheers.