Not including septic of course because that;s an easier run.I would do a sewer scope even if just to know if/where there were branch lines or moderate blockages.....or even the bellies.

Only "A" markets where 10 x 20's rent for $130 or higher will be able to justify the increased building costs.

Quote from @Jeff S.: Wow.

The other side of the line would be someone looking for a nice place to live and just subsidize their housing costs with adjoining unit(s) rents.

Nearby new build 3/2 SFRs start in the mid-200's, and there's a lot under construction.

Quote from @Kay S.: All this.

Anything much higher and you'll find the #s start to get tough.

@Joe S.

There is a new apartment development on S Central right off of 70

Other items such as having accounts in a foreign country.If you are single/married, with a few W-2's, interest/dividend accounts with one rental property.