So if those three units are 75% of the square footage then 75% of the closing costs and mortgage interest and taxes would be considered business expenses.

Aside from the standard BR/BA count and square footage, I always focus heavily on the listing pictures for any comps I pull in my area - finding a comp that's as close to your property's condition and finishes will give you the best apples-to-apples comparison possible.I also wanted to second @Tim Swierczek's input: nobody in Minnesota likes moving in the middle of winter.  

Square footage?  

As Marshall said we will need to know breakdown between residential and commercial, exact business types, and square footage + income breakdown for residential and commercial units.

Right now between my house and ADU, we split the water based on the square footage. 

@Cole HarrisKeep in mind that square footage has a lot to do with pricing as much as bedroom count and/or revenue. 

Basically if there is no "living room" and there are no comparable properties with similar square footage and bed/bath count in your area the property becomes difficult to comp or sell and lenders will not be able to use it as collateral for a loan Excellent point.

SBA loans can also be used to purchase existing real estate, as long as at least 51% of the square footage is owner occupied (so occupied by your business). 

How many br, ba, square footage?  

Collin when you say Cabin style are you talking about actual log cabins like we have out west in the MTs of Montana  Idaho Colorado etc..