Send me a PM - our business specializes in designing flips and STRs across the US!

It's too much like the hospitality business rather than a rental. 

And this does not even involve business or real estate!

Dig and remove around 200 square feet of an old concrete driveway, frame and lay down the concrete (concrete will be ordered from concrete supply business) and complete a brick ribbon around the driveway.

See responses to your questions below: Correct, California is uniqueTo qualify for REPS you need to meet a number of criteria, including (but STRs that meet IRS criteria generally don't need REPS to leverage tax benefits): More than 50 percent of his/her time working in real property businesses; AND, More than 750 hours of service during the year.

Trustin your PM partner is important and they will follow your lead, so don't expect them to provide you with your business plan. 

If I put myself in the shoes of the outside partner/investor friend, I would be very concerned because: 1) unclear and/or potentially conflicting business plan, 2) even with clarity in the BRRRR business plan, unclear in the viability of pulling it off with these market conditions, 3) the chances of dispute seems very high, especially if you're going to live in. 4 years ago, I went through a  similar thought process when purchasing an investing property with mainly my family money, while considering an outside investor to rehab for higher STR ROI... 

If it's a QM you won't be able to close in a business entity like a LLC, although in some cases you can transfer into an LLC after closing.

If the handyman can’t get those things done in that amount of time they have no business being a handyman.

You have to be a serious individual that takes care business.