Cash flow vs. heloc newb questions

[Nikole Johnson]

I bought a 6.5 acre property and built a new 2 bed, 1.5 bath, 3 car garage universally accessible SFH entirely in cash in very rural Maine. I chose the town because my brother (a retired builder) lives there and he generously built the property himself so my only investment were permits, land, materials, as well as foundation, well and septic which we hired out. My father wants to rent said house above market value for $2000 p/m in order to be near my brother in his old age. The rent my Dad offered is Triple Market value. My total cash investment was 110k spent over 4 years. I have no idea the Appraised value of the Sfh as the town is rural with nothing comparable in structure to it. I could just keep the place free and clear and collect my above market rent until my father passes (likely any time as he's 76), at which time I might get 7200 annually market value rent if rented full time or $6000 annually if rented seasonally to hunting parties. My insurance and taxes are ABout $1000 annually. My brother has volunteered to manage the unit if I rent it out to others outside my father. I could get a heloc and try to buy a rental property in a better location which would reduce my positive cash flow to maybe $100 p/M. What would you advise?