Some of the upgrades you mentioned (specifically the smart tech stuff) only help for new home buyers (window shoppers).

There are so many dynamics like specific location, size, square footage, type of home, ARV, utility hooks and a dozen other things.  

In this case, it ultimately depends on the specific policies of the apartment complex or landlord.Some landlords may consider the overall average credit score of both applicants, while others may require each individual applicant to meet the minimum credit score requirement on their own.

There are work arounds to save money but it's always property specific solutions. 

In regards to learning more about real estate and maybe how to answer those questions I'd recommend listening to BiggerPockets (Rookie and Real Estate Podcast), there are also some market specific real estate podcast you can check out depending on the area you want to invest in. 

Pick one that is commenting on your specific situation and DM them.

The Website does not seem to work for me.

If that person is an employee of one specific bank/lender, it's common for them not to have any idea which hits are "their" hits, and which come from Fannie Mae, since they only ever see the rate/fee schedule from the one place they work at, and they aren't typically labeled that way, it just says "2-4 unit cash out:" and lists the amount of the hit in basis points, without specifying from whence it came.

Newbie here and looking for some specific advice on investing in our first STR:*How can I find a mentor? 

We specifically talked about trimming the tree in the left from corner, but trees all over need to be trimmed.