Since this is being done within an LLC (as it should), and since there are different classes of membership interests (2 that I can ascertain), there are multiple factors to work out, some of which apply even when there's just one class of membership interest:How initial capital contributions, for each given class, are booked.How subsequent capital contributions, if any, for each given class, are booked.How member loans are booked.How each member's capital account will be handled pursuant to Treasury Regulation §1.704-1(b)(2)(iv), and how reevaluation of said accounts will take place per Treasury Regulation §1.704-1(b)(2)(iv)(f), to conform with §1.704-1(b)(2)(iv)(g).How distributions will be allocated, including profits and losses, along with any resulting adjustment of percentage interests.How tax allocations will be handled - and if the book value of any company property is adjusted per Treasury Regulation §1.704-3, how that affects member allocations.I have not even covered every item that must be addressed (including voting rights, depreciation allocation, cash flow vs liquidation allocations (as in "when we sell a property - who gets how much of the appreciation, but what about the recapture, etc, etc.")).Insufficient information... and it's time to meet my wife for dinner.

I have heard of this but it was coming a lawyer that was going to help the company I was working for go and get the funds and take some large percentage and what I was hired to do.

It's better to put those percentages a little high then too low.Did your calculation include property management?

It all depends on how the bylaws are written but as they are most of the time boiler plate decs it is pretty standard that you pay the prorated percentage your unit makes up based on the decs.  

Of course, the broker would get his/her percentage.

What percentage is that?

@Anthony Talpak,I'm not sure if anyone addressed this yet, but the interest charged by a lender (private, bank, hard money, etc) is calculated annually (99% of the time), hence the term APR (annual percentage rate). 

A better question to ask is "what percentage of your client base is made up of real estate investors" or "how many real estate investors do you service?"

What percentage is reasonable for a fee?

The reason being is that they know there are people that have preferences for one reason or another, and they don't need EVERY customer, just a percentage of the customers.