If you work with a local community bank or credit union or some lender that doesn't sell to Fannie/Freddie in the secondary market, their guidelines and pricing could be different on this matter. 

It allows buyers to qualify with different guidelines than what a conforming loan would require.

It can still work in niche situations but I think it is a grind and you gamble time and money. 

Definitely a good question that would require a little more homework and guideline digging to know for sure.

I have a nearly perfect credit score and I'm gambling on that for my first project.

What are the rules or guidelines in California regarding rent payments when a rental unit is temporarily uninhabitable due to repairs?

This includes (but not limited to):-Quiet Hours-What spaces can and cannot be used-Guest policy (make sure to limit days in a row and in a month)-Pet policy (even if you don't allow pets, if someone has an ESA animal, it would be good to have guidelines in the event they surprise you with one, otherwise you are SOL and of course take into consideration fair housing laws)-How is trash put in the cans (in bags, not just thrown in) and when can trash cans be taken to the street and put back-How is the late free structured (one time flat fee or a daily fee)2.

Or are there other metrics/guidelines/rules of thumb I could use to help gauge that part of our timeline?

Its complicated and if you violate any of the IRS guidelines it will negate the 1031. 

When using a lender, you'd be locked into their specific guidelines and sometimes, that's not the best for you.