If it takes 120% worth of PPT to buy an invoice and if the 50% of PPT token holders buy invoices, the maximum capacity of the platform would be approx $230M at the moment. This means that PPT needs a liquidity pool of this size to pay invoice sellers.
I can't seem to find any specific info on where this is coming from. Some have said that Nico has arrangements to borrow for this liquidity pool at a lower interest rate like 0.5%/month. However, if Nico is able to obtain a line of credit for $200M+, why wouldn't Nico just do everything himself and cash in on the spread?
In the interview he mentioned that there are many walls that prevent an average person to create a company like populous. The banks enjoy the monopoly they have over the market.