sentence: while the investor 's need for high rates of return on any given investment can thus make angel financing an expensive source of funds , cheaper sources of capital , such as bank financing , are usually not available for most early-stage ventures geographical differences us geographically , silicon valley dominates the destination of angel funds , receiving 39 % of the $ 7.5 b invested in us-based companies throughout q2 2011 , 3 -- 4 times as much as the total amount invested within new england .