Same total price on two parcels, and the carrying math decides it

I have been circling raw land for about a year and I finally have two things I can actually buy. Same money, very different bets.

Parcel A: 34 acres, $4,100 an acre, $139,400. Nine miles past the last recorded subdivision in the county, gravel county road frontage on about 600 feet, currently hayed by a neighbor under a handshake. Tax bill last year was $2,050 because it carries an agricultural valuation, and whether that valuation survives a sale depends on the state and the county, which I am still confirming in writing.

Parcel B: 11 acres, $12,500 an acre, $137,500. Sits maybe 1,200 feet outside the current sewer district boundary, paved frontage, three sides already platted residential. Tax bill $3,400 and no ag valuation to lose.

Ten year hold, taxes flat for the sake of argument, A costs me about $20,500 to carry and B about $34,000. Add a survey and title on either, call it $4,500. If I assume 5 percent a year on both, A ends up ahead on net dollars purely because it is cheaper to hold. But that assumption is doing everything, and I do not actually believe both parcels appreciate at the same rate. B appreciates if the sewer district moves 1,200 feet in ten years. A appreciates if the whole growth direction of the county holds for twenty.

So the real question is whether I am buying a shorter, more legible bet at double the carry, or a cheaper carry on a longer and vaguer one. I have a district capital plan that shows a study, no funded extension. I do not know how to weigh a study.

The other thing I keep stalling on is that I would have nothing left after either purchase. No reserve for a tax bill that reassesses upward.