Starting with the question of whether you can subdivide the parcel without paying off your current mortgage, the  question is what is the home on the smaller parcel worth, rather than focusing on the current ARV of $325,000.00.

It is just easier to cash out of the deal and get everyone's name off the mortgages.As far as contracts, use the TREC contract.

They have a paid off Condo (1/1.5) in a 55+ community, not the most desirable area so worth approximately $100-115k.

My husband and I were recently connected with someone who would like to sell their townhome off-market (to avoid realtor fees, specifically).

I have analyzed tons of syndication opportunities and the name "Simple Passive Cashflow" would be a pass right off the bat. 

As I don't have large down payment, I am thinking to start building a portfolio with finding off market deals that have equity and do bit rehab/renovate and later get refinanace to pay off HML with a traditional lender/DSCR loan. please share any thoughts on my plan and any lending resources.

If I build a basement apartment, can I write off a portion of the expenses it took to build the house when I go to do my taxes for 2024?

It's like an 80% off sale.

Show them you are interested in any and all houses (not just theirs) and that they need to expect a trade-off.

It sounds great on the surface: use a 0% APR intro offer on a credit card and then pay it off when you sell/refinance the property.