I accept them and mitigate the risk by (a) screening the animals, (b) having a solid set of rules that are quickly and fairly enforced, (c) regular inspections, especially for cat units, and (d) charging a monthly pet fee.Let's say I have five single-family homes.

@Luis Maza Just like there are quality contractors out there and those that are not, the same applies to wholesalers.

Any rule of thumb to use while analyzing?

They will know setback rules, road widths required, easement documentation for road and utilities, postal box and bus stop.  

There are some ways around the rent control issue in my location by making the ADU an STR (not a long term rental) and apply for a license to STR on the ADU.

One of my clients recently purchased a 4/2 single family house that was positive cash flowing, hit the 1% rule, and was able to execute a full cash out refinance so it was a clean BRRRR!

3) Lastly what would happen if I applied for a construction loan application that pertained to Real Estate?

I suggest you understand the 50% rule.  

If you are seeking a more traditional DSCR type loan, then typical guidelines apply; Credit, Liquidity, and Experience. 

I have a Wynd sensor in my units (mention that we have it and it's 99.9% accurate in our emails), put it in my house rules that it is a $250 fine, and have a sign small above the detector with the same language.