The protocol does not limit borrowers to propose a certain type of financing (e.g. receivable financing). The borrowers can propose any form of financing so long as the repayment schemes are supported by the smart contract.
There are two repayment schemes supported by the smart contracts during the beta stage:
Amortised - Principal and interest are repaid at each repayment cycle
Balloon (or) Bullet - Interest is repaid at each repayment cycle. The principal is paid back at the end of the loan tenure
Having said that, there are some examples of financing types that are more common than others:
Working capital financing
Line of credit
When preparing to propose borrower pools, borrowers are strongly encouraged to describe the type of financing being proposed clearly to help investors properly assess risks associated with each type of financing.