Delta has round-trip flights from Portland (PDX) to San Jose del Cabo (SJD) for $314-$340 with a connection. Flights April to May. Departures on Monday and Sunday. Origin/Destination reversible. Flight may be marketed as a Aeromexico code-share.
A Carry-on bag and also a personal item is allowed for free on Delta. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.