If the terms of the modification materially affect the terms outlined on the Deed of Trust your attorney/title company might suggest also recording the Modification. 

The Clawback does not have to affect him other than some reporting requirements

Unless you can find good repeatable land deals you'll never be able to beat the investors flipping and BRRRR 'ing distressed properties.

There is a moratorium right now for new services that that could possibly affect you.

It affects flipping as well.I’m running numbers on a CT property now and I’m amazed.

(New PA law requires Ten years if the property is less than a half acre -see the affect of PA house Bill #352 lowering Quiet Title times via Adverse Possession to ten years for some PA residences.)  

Once you get that refinance work on the repeat and build that momentum. 

A few articles say it's a soft pull on your credit, but if you soft pull multiple times, it can affect your credit negatively. 

Once rented, we can refinance with a traditional mortgage, pay off the HELOC and Repeat.

I contemplated the idea of just changing the design concept to have it be attached to the main home, but even in that scenario, the explicit CCR's against even renting one room seemed too controlling to be sane, considering that if this worked as we wanted, there were like 200 other nearly identical situations with lots with homes in that neighborhood that we would have just wanted to rinse and repeat that strategy.