Multi Vendor – Cash Only – Sale Credits Capability

I am starting to chose which plugin to use but need to check if there is such a process existing already.

We plan to have vendors do cash only transactions to their customers not in the US, but in the Philippines where a lot of cash only transactions occur. These Vendors also ship the products and collect the cash payments.

We plan to charge them 3% to all sales posted on the site. But before they sell, they need to do the following:

1.) Deposit the 3% of the planned sale they want into our bank account.
2.) We verify that the deposit is made, then we give them sale credit in return. These credits will enable them to post and get sales for the products using our website.

A. ) For example: if they plan to do P10,000 worth of sale, they need to deposit P350.00 to cover our 3% fee. (This should feel like they need to do a “load” to the website in order to do business.

B.) Once the deposit is made, Admin will give them the sale credit amount according to how much they deposited. (P150 for P5,000, P300 for P10,000, P3000 for P100,000)

The % fee is of course customizable for WP.

3.) Once the “Sale credit” is then given by Admin, the Vendor can sell anything until the sale credit is met. Then they should “load” again.

Is this even possible, or available to any plugin? If not, is there something similar, that can protect the owner of the site against vendor cash only fraud. (I.E. vendor cancels the sale to avoid giving commission to the site)