Such configurations will put you directly in charge of the funds with the ability to sign contracts and handle expense/income transactions without 3rd party paperwork, delay and per-transaction fees.  

I'm probably misunderstanding but you might want to get in touch with a local GC and architect to give you an overview of what your projected costs might be.The forums are great for pointing you in the right direction, but there are NYC ZOLA (Zoning and Land Use Application) configurations to keep in mind as well.

In order to be a comp it truly needs to be comparable -- "just the same" but not in the same neighborhood, configuration, amenities, condition is not truly "the same".

Use this to gauge both interest in configuration and price; to determine what effort you put into this building.Great project. 

@Yuki JonesWhat is the exact property you trying to buy (including condition, configuration) and where?

While there may not be an operating condo association, the lender you ultimately go with will treat the property as an office condo because of its configuration. 

A lot of 10 year balloons taken out near the peak in 07 are coming due so there may be more opportunities in your market.Not sure what the configuration of the property you are looking at is but you might be able to subdivide the lots into 3 lots and get 3 separate conventional loans but it may not be worth the headache. 

Like my new construction stuff I get pre configured they just drop on my site like a leggo set.

Permitting can take anywhere from 60 to 180 days depending on design of the ADU, the configuration of that lot, environmental conditions, and other related development issues and matters.

The type of home (SFH,MFH,HOA involvement, etc.) and the configuration of the property (adequate space for the needs of the animal) will factor in.