Incurring losses every year will mean that the losses will be suspended and carried forward and will offset future passive income.

The current way the studs are built is not up to code, so they have to rebuild the entire structure of the kitchen wall This is not uncommon especially when renovating an older home and when budgeting you should also carry a very heavy contingency for unknowns. 

Its great that the seller is will to carry a note in a seller 2nd as well, that will help reduce your require monthly payment with the right lenders.

This setup alone feels like a solid foundation for financial freedom.Here’s my dilemma:While I understand that my mortgage interest rate is very low (2.8%) and there are tax benefits to carrying the debt, I’m wondering if it might make more sense to aggressively pay off the loan.

Reason is a Heloc generally carries a higher rate on a shorter term and "Can Never" be used as an "Asset, or for PITI reserves" which are both required when you buy an investment property. 

Make sure you ask them good questions, make sure they carry insurance and that they are available year round. 

I know there are a lot of options, especially since they are family and willing to carry the loan. 

Auto limits of 250/500/250 and Homeowners liability of 500K should be the minimum you carry.

But ultimately the responsibility lies in my hands.I jumped on a seesaw of risk hoping that the momentum would catapult my bank account into six figures only to find out the hard way that flipping houses isn’t as easy as I had predicted.This house was purchased for $64,000 with an expected rehab of $100k to $120k depending on how much work the dilapidated and neglected house needed.The midwest is lovely but the houses carry the weight of weather storms nearly a century old leading to more damage than a beginning investor could expect.The appraisal came in at $225k for my lender meaning our all-in cost would be around 85% of the sales price worst case.

You have the means to purchase and intend to offer owner financing (you) to the buyers of your lots.That sounds pretty straight forward as long as you are able to carry the loans and deal with any defaults.I don't have a background in raw land deals, so that's all I got.Thanks for the feedback and I will keep these things in mind as I move forward.