I know I could threaten to move our office, but that is a huge undertaking and fairly unrealistic in a town our size.

I actually love this idea, but it is a serious undertaking.  

Honestly, developing the project myself sounds fun/challenging/rewarding but I know I do not have the wherewithal at this stage of my career to undertake such a project.

This is a possible large undertaking so looking for experience and/or advice.

Experience,pure and simple.Always have a GC with you for your first dozen times you look at properties and write down everything they say about how much money per square foot it would cost to repair or replace the bones(roof,plumbing,electrical,foundation)and upgrade redecorating costs.After a while it will come naturally to you and you won't need a GC by your side every minute during evaluations.

Anyway,  to find 30 or 15 people with capital I think would be a huge undertaking and an even bigger mistake, but possible.  

Developing a park from scratch is not an easy undertaking even with the partial process started.  

@Alek LupaWhile there are always folks who will live in a basement, this type of accessory apartment is generally less desirable than an above ground unit.In addition, digging down a crawlspace and underpinning the foundation is an expensive undertaking (provided it is possible, sometimes houses have crawlspaces, rather than a basement for reasons other than economics).  

New investors should not undertake the process alone and think they'll cross all the "T"s...you might get away with it or you might have a hungry attorney make your life a living Hell.  

She's not acting as a hard money lender, who does undertake risk and thus, I assume, can charge more.