I read an article about how buyers love smart thermostats, doorbells, etc...I’m wondering if adding some of those will make the property easier/faster to rent.

I would use the cashflow from the properties to help you pay it down faster and build a big reserve.

The general goal with the refinance to recover your rehab funds, which could allow you to repeat faster

After all your landscaper already has all the equipment, has more experience and can do it faster and better than you on a consistent basis.

Same price, faster results.

The big difference is you are super leveraged so the return happens a lot faster. 

Targeting more equity is the faster way to boost your net worth than $1000 a month cash flow.Instead of buying a cash-flowy house in the midwest with my $40,000 cash, I signed a construction contract in a good neighborhood, and after 18 months, that $40,000 turned into $110,000.

It rents for $3000 every month, and with an appraised value of $375,000 we refinanced using a 1st Lien Position HELOC strategy to pay down the balance MUCH faster while have equity accessible to take advantage of opportunities.

Anyone out there faster or is this common?

With your life's experiences and financial capability you can go much faster than someone much younger.