This might be an obvious response but how are you going to remotely access the lock if there is no wifi? 

Your friend should have either received a statement monthly or had access to one online.

And correctly..you cannot co sign as a primary if it's occupied..2+ units can sometimes require larger down payment (as you've found) another option could be to access equity against another property..check in with @Joseph Chiofalo for potential lower down payment options..might be able to get to 15% down..Good luck! 

Since you are new, I recommend staying with flagged properties that way you get support from the franchise and access to loyalty members.

My goal is to help California: Homebuyers with their down payments using equity -- not debtHomeowners access their home equity -- without additional debtInvestors: Participate in home appreciation -- real estate investing without tenants or management.It's called equity sharing.

Regardless if you have skills in finding deals or have access to capital, without a good network, you won't close the deal.

High point for it's accessible entry point3.

Considering this, how would you be able to handle the potential objection of the bottom unit tenant complaining about AC/heating since it's likely that the main unit tenant will have access to the thermostat?

He tells me he will upload the full accounting to an online account I can access (as agreed to in the JV contract) by the end of the week.

With free bussing available, it's essential for people to access public transportation for work.