You can, for example, control a $1M asset that appreciates $30-50k per year with a $50k down payment plus closing costs if your DTI is in good shape.

If you want to grow, then scaling within control is good.

SFHs are largely exempt from many regulations such as rent control.

We understand that not every lender will provide us with a commitment letter due to risks outside of our control (the market, covid, the borrower, etc).

The answer is that if the lender that's doing the hard money loan is only funding the purchase and not the rehab, they then have less oversight of the project since they're not doing the draws, and thus not seeing the progress of the project and having control of the funds or draws from the rehab to make sure the project is progressing.

But, this has absolutely nothing to do with living out of a line of credit rather than a checking account.Even not counting the opportunity cost credit given in the analysis for the “reserve” theoretical investment, the additional nickel and dime fees associated with the HELOC will eat up any savings.Perhaps you became much more vigilant at controlling expenses when you decided to use the HELOC to pay your everyday bills.

Which gives me much more control of the money/asset management than just leaving it in the market for alot more years.

Better financing, more control, don't need as much down, etc.  

Keep in mind rent control is 1 thing, its a laws for existing tenants but some city's like Newark are so strict that you must get approval for what rent can be even after a tenant moves out and new ones move in. 

What's the exit strategy if any, for the investor, given that, with 50%, he has no control and the market there is illiquid, especially when the HELOCs out of North American properties are much more expensive.Properties in Costa Rica are already expensive and I've tried many times to make a potential investment there work and it's never worked with the figures.