American Airlines has round-trip flights from Dallas (DFW) to San Jose del Cabo (SJD) for $204-$218, NONSTOP. Flights February, March, April, May, June, July, and September. Departures on Monday and Tuesday. Most flight pairs are short midweek trips unless you plan on staying more than 7-days.
Carry-on bag is allowed for free. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.