Here's my suggestion...
There are 12,749 notes on folio that meet the following criteria:
- YTM >20%
- FICO >660
- Never Late=true
- Status = current or issued
These notes total $856k of principal and $9.3k of accrued interest. They are for sale @ $902k. Because I'm a nice guy, I sorted the results by YTM decending to get to your $250k working. You would invest in the top yielding 3726 loans, win a minimum 22.7% YTM. You'll pay an average mark-up of 2.8% so your first month and a half's interest will get chewed up but, after that, you'll have a well diversified portfolio.
If you want to only buy notes with a positive FICO trend, there's still $390k worth of listings with YTM >20%. You'll pay a higher premium but, after the first few months, you'll be back in the black.