But I know more comps are probably needed(assuming it sells).ADUs are definitely expensive to build.

They are building another section of the same subdivision down the road, but is only for buyers no renters.

This is a mixed-use building with 3 residential units and 1 commercial unit.

I understand everything is situational based and it could be several different factors but it likely has something to do with the area you're investing in. 

number of tax parcels, number of physical buildings?

Good Morning Siri would prefer using other ppl money to build your nest egg faster 

Hello, we had a tenant move out that we inherited with the building.

I don't want to have another full time job and neither do a lot of passive investors out there.I'm working on building a longer track record because I know it will help me in the long run to earn people's trust.  

Just search for "Scottsdale building permit fees". 

I used that color scheme on my recent BRRRR and notice that color scheme on new build homes they are building in my  area.