> I have seen many advisors working on a success fee model. They take a %age of funds raised as success fee, %age of revenues generated as success fee.
You have to be careful with this. Very few advisors are registered broker-dealers. I mention broker-dealers because only registered broker-dealers can legally take a cut of funds raised in return for help in fundraising. That's US law, but some other countries have similar restrictions. (You care because illegal fundraising scares off many investors.)
For example, https://www.sec.gov/divisions/marketreg/bdguide.htm specifically calls out "Engaging in, or finding investors for, venture capital or "angel" financings, including private placements;" and says that B-D restrictions apply when "Does your compensation for participation in the transaction depend upon, or is it related to, the outcome or size of the transaction or deal? "
Google "registered broker dealer definition" for more information.