You can make these three types of sales transactions using the Accounting module.

1. Customer Payments (in Cash)
   To put it simply. You make payments from customers in cash. Customer payments do not support any crediting. This goes directly into your savings or petty cash account.
2. Customer Invoices (on Credit)
   Invoices allow your customers to buy with credit and pay later.
3. Invoice Payment or Partial Payment (Credit adjusted from Debit)
   When a customer makes payment of only a part of what he owes. Useful for making sales with installment features.

In any case, the accounting module will adjust balances in real-time and provide you with the updated information.