Characteristics of equity partners / private money lenders

[Erik W.]

I am an experienced land lord of SFHs and plexes and have done the occasional flip.  Now I want to move into multi-family residential investing.  Initially, I'm looking to take down a couple of "smaller" deals (30-50 units) and then if all goes well move into larger scale projects.

While there are many podcasts and blogs on sourcing private money I haven't found anything specific on the capacity of the money providers themselves such as:

1) What is the minimum investment amount I should require from a money provider that makes the most sense for apartments?  I don't want to end up coordinating with 40 partners who each chip in $5,000 just to make a down payment on a smaller apartment complex.

2) Liquidity / time it takes to access funds.

3) Length of time I should require the funds to be invested in the deal before we "Cash out / Buy out" any one person or the whole deal.

In general, I'm thinking that the bigger the deal, the larger amount I'd want to ask for from each investor and the term to leave it in the deal would get longer.  Any advice from experienced investors or links to resources are appreciated!