Being a Private Lender to Flippers - Real Numbers???

[Tony Hill]

I am considering the path of being a private money lender for fix and flip investors (I don't have the money to lend at this point, just doing the research).   

I am curious as to the reality of lending out short term loans to flippers (IE 10% for 4-6 month terms).  Assuming I take the proper legal precautions and lend to someone with a solid track record of flipping quick and profitably, this seems like a no brainer as it would return 20-30% annually.  

Am I missing something?  What are the real numbers I could potentially expect from doing this?  

Thank you!