Network with local investors, undertake extensive due diligence, and develop a clear exit strategy.

The first indication is you spent $290k for $1800 cash flow or a 0.62% monthly ratio.Rent $1800 - PITIH $1480 - $180 (pm) - $90 (vacancy at 5% which is lowest i ever allocate in my underwriting and likely low per the OP description of a lot of new development) = $50 for all other expenses.Maintenance/cap ex on 4/2, 2100’ will exceed $300/month even in cheap labor markets on sustaining basis.  

I'm not motivated, but the homes needed work I didn't want to do or I did if for strategic tax or debt shell game reasons.

I would guess that you have little or no experience running any kind of STR, and now want to get that experience on the back of someone else's investment, with little or no personal skin in the game, and that's not a good way to build an investment portfolio.

More like  2X to 5X the cash out.. these are done with builder developers on their deals So put out 300k get 300k back in profit plus the interest rate. most small builders/ developers need to have a equity partner so you just do both you lend the money and are the equity partner.. pretty clean..

I know many of us didn't get into this game until later in life so my hat's off to you.

But from my limited time in the game, I’ve found that my complete lemons are cash cows a few years later as market rent comes up well and my cap ex fixes a few years ago have paid off.

(FYI - this was an SB9 "two unit development, not an SB9 lot split). 

Now I agree the 4 will cash flow better than one will but I also look at it from risk of 4 properties will have higher maintenance costs and lower priced properties tend not to appreciate as well as a higher value assetI am also in it for long game and managing one is easier than 4

Hopefully, based on actual field measurements, past project data, and estimating software, your contractor can develop a detailed estimate that lays out the cost of labor and all materials for each phase of the project.