A PE firm approached me to assist them on a deal they're evaluating which is in an industry I have expertise in.
They are considering investing in a firm that is doing a roll up but would like someone independent of management to "help them on this". They would like me to propose how I can help. I don't really understand what they're asking me to do or what I terms I should propose.

Are there standard terms for an engagement like this? Should I ask for cash or equity or a bit of both?

Practically, how I could add value would be:
1) Researching the industry - growth/fragmentation/availability of suitable targets
2) Multiples and availability of senior and Mezz.
3) Deal sourcing strategy
If they decide to go ahead, I feel I could add value in deal sourcing/closing.