That's no cost rolled into the HELOC either. 

New loan - ~70-80% of the ARV (126k in your example - paying yourself back the 100k, plus 26k extra)Closing costs (generally rolled into new loan) - lets say 4k for example (you should shop around to see best option)Total loan amount that you are paying back monthly - 130k (plus insurance, property tax)Dont forget about the seasoning period though!

@Alyssa K.Rent a push behind diamond grinder.

Go through your rent rolls to see who has the worst payment history or maintenance issues.

We’ve also considered renting all three units, but are very concerned about the eviction moratorium and CA’s continued push toward renters vs landlord rights. 

Vacasa is rolling out in Atlanta and also I spoke with Evolve(.com) - Vacasa is around 2x the commission but seems to be full service. 

Instead, I'd like to sell this property and take the proceeds and roll that into a rental that's closer to me and use whatever tax advantages I can to assist me.I'm confused with how the 1031 works and was hoping someone could explain to me how to "use" it.  

The purpose of these are to be quick and help investors recover their cash so they can roll into another deal quickly.  

@Salvatore LentiniI've always been proud of the thought that I'd have my primary residence paid of before the age of 45, but then I refinanced at the age of 35, which pushed that pay off to 50 years of age.

As a builder, you should lock in material prices under a contract with your supplier or put a stipulation in the sales contract that pushes material increase expense on to the buyer.