Our first tenant stayed for 2 years and 8 months, and we've just recently moved in a new couple. 

A couple of times a year you should power cycle both your modem and router. 

They ask for 50% upfront, material costs (or combination), and they prefer cash. 

I discussed the impact of our beach STRs in San Diego (is there a more drive to destination with Los Angeles (12.6m), Tijuana (2.3m), Orange County (3.6m), San Diego (3.3m) all within a couple hour drive of our STRs?)

Here are a couple of SEC 8 specific criteria...1) If their court records or pay stubs show any record of garnishments, be careful because SEC 8 ignore garnishments and the applicant will have trouble paying their portion, just like any other tenant would.2) If you see an outstanding landlord judgment, call the caseworker to ask when the tenant first was accepted into the program.  

California has a couple of additional hoops post foreclosure sale, if its a real foreclosure sale but its still pretty standard.

Couple takes on this: Generically speaking, yes it often does make sense to increase your loan amount for monthly savings. 

I used a HELOC to buy a couple houses.

I am still evaluating if this is the best investment for me to proceed with as we get further through due diligence and I will keep everyone updated on how things go.A couple things come to mind.1.

(So, do you really have a PREFERRED return?)