About 2 years ago I became heavily involved with P2P lending. I began using LendingRobot to handle secondary market trades however it became immediately obvious that it was lacking certain feature. One feature, in particular, that was missing was the ability to immediately sell notes as soon as they began to demonstrate deterioration. So I built
PeerSpectus :
http://www.peerspectus.com/. It includes several strategies but one of the most important is the 'Watchman'. It continuously monitors the user's notes and immediately places them for sale at the best price when any note degradation is detected. I not sure what to do with the platform but it seems to return 30% better than using LC by itself. check out the website for more info - and I would be glad to show the actual PeerSpectus backend to anyone.
I'm also about to release a Website and API which allows the user to price a note on the secondary market. After a user enters (or sends via api) all note info, it looks at the entire secondary market and finds the notes that most similarly match the given note. It returns the lowest, median, and highest suggested prices for you note along with the supporting data of the most similar notes.