Ultimately you need to find out if you and them are a good fit. Think of it like dating - ask many questions.
Firstly, there is investment-fit:
- Investment stage (seed / series A / etc)
- Sector / vertical (A.I, Agriculture, Manufacturing, etc.)
- Traction - Do you have the numbers they're looking for
- Returns horizon - how soon do they need to exit / cash out? Can you reach there in time?
Secondly is the culture-fit:
- Do you like them / their team / their values
- Do they like you / your team / your culture