Wait until you are married and then form a plan for pay off. 

Then have them put together an operating pro-forma based on the property.  

They deal with stock brokers and others in investing circles and they know that if they are shown a deal with numbers, interest rates, profits, expectations of a pro forma accounting summary that the information you hold out is the deal, it is the representation.Problem is, investors can get stuck with a property, you can have cost overruns, you can fall behind due to weather or a number of issues, you can lose a buyer, deals don't close, I could go on, but you get it.

Would you still form a trust for each property if the value is relatively low - <$50K each - or would you group them?

This should be taken as an example of why you cannot normally trust CAP rates provided by third parties - particularly the Vendor's pro forma / memorandum of offering where there will be motivation to provide a rosy picture.CAP rate is only a single metric and like other metrics (GRM, Price per unit, etc), it is insufficient to base a purchase decision upon it.

The best way to do this is to form a solid relationship with a general contractor you can trust who will be doing your reno work upon acquisition and have them walk the property with you when you tour for the first time.

Well, worry no longer: The State of New Mexico will allow 10 investors to form a syndication and raise up to $1M and be exempt from SEC and state securities regs.

Does anyone know of any robust templates for creating pro forma financial statements for real estate businesses?

You should be able to find some historic data on appreciation rates for the Greenpoint area to support your estimated appreciation on a pro forma basis.As a side note...estimating appreciation is a great exercise, but there is much more to consider on an an asset and project of this type. 

An example from my early investing with less cash down: i called around for a buyer's RE agent who would accept his commission in a form a note with payments over 60 months.