How to negotiate economics as first hire to an independent sponsor

Thinking about joining an independent sponsor as a principal (3 yrs associate experience at a MF, 2 years BB IB).. would be taking a significant haircut in cash comp to $200k base which is more than half of what I would be making at a MF but I would be joining as a principal and the first hire to the independent sponsor (which is just the partner currently). What are the economics I should be asking for in terms of carry and bonus? Cash comp is quite limited beyond the base but I was told I would get carry and equity but not sure what is typical for a principal. Is 20-25% of the carry reasonable, and should I also ask for equity and how much? The team is likely just me and the partner and potentially several operating advisor / partners. Would really appreciate your advice!