1991 Mazda 626 with difficulty starting

Does it have an aftermarket radio? Or alarm? I am thinking the car has a parasitic drain from something connected to the battery. The 2 items I mentioned are very likely culprits. But a good mechanic can check for this and pinpoint the draw from checking fuses. His time won’t be free, but then neither are car batteries.

That’s very interesting! Yes, it has an aftermarket radio. However, that radio has been there for a good ten years… Also, the battery lasted for six years. It’s a worthwhile thing for me to look into, though. So, thank you for your input!!