I'm a commercial lender and we do this sort of financing a lot.  

Since you have, or are planning on having, so many paid off you could look into doing some sort of bridge financing.  

Whether the partner wants a split of the monthly cash flow or is interested in plowing it all back into another deal with you is something else to sort out.Finding a partner or private lender can involve a lot of negotiation and the terms are only limited by the imagination of the parties involved.

Do not be afraid to walk if this is not sorted out in advance. 

As far as not being able to freely dispose of your property, that will never happen (unless the seller happens to choose to sell to a buyer who is using financing of the sort I just mentioned).  

She is going to email me all the information later but I don't have the capital to purchase all these properties unless I get some sort of super huge loan.

I was wondering how people would come up with that number, I am assuming there is some sort of formula for this, I know that a part of it also has to do with knowing your area, which just takes time and effort, I understand that part.

I am trying to get rid of a home that I have and this Real Estate Agent does some sort of FSBO.

Unless you're buying this at such a smoking price you wouldn't want someone else to steal it, I would not close this until it is sorted out.

Maybe you could work out some sort of JV (if there's enough equity in the property) to give you some cash up front and also when the other investor sells it.