I'm also new to lending club (started August 2015 with $2500). I have my automated defaults set at 5%C, 15%D, 50%E, 20%F, 10%G. I do not discriminate based on what the loan is for. In just a few short months, I have had 2 notes go into the grace period, 1 F ($75) and 1 G ($150). The F person must have taken a separate loan out and fully paid off my loan. The G person has had plenty of troubles and there are 20+ collection logs of attempting to contact him, and some say "buyer promised to pay" whatever that is worth lol.
So far I am at a -1.13% return, however, this is very short term and if this guy somehow comes up with the money I will be back into the positive.
I started out doing $75-150 per loan to get my money invested quickly. I had quite a few loans fail to close and felt like my money was just sitting there and not being invested. Now I have my investments set at $25/loan to decrease variance and continue to get money invested quickly once I reach $25 in my account.
I haven't purchased or sold any loans on the trades, as there are fees and people often request a premium for what the loan is worth. My estimation is this is a less profitable route than purchasing new notes.