If you're comfortable with a drill, a ladder, and reading a wiring diagram, a straight opener swap on sound header framing is within reach for a patient homeowner. Where people get into trouble is the safety sensor alignment and the travel-limit setting - get those wrong and you've got a door that doesn't reverse when it should, which is a real hazard, not a cosmetic miss.
We'll be honest: if your house is near the older end of the area's build range and you're not sure the header will take the new unit's weight without inspection, that's not a DIY call. A header failure under a running motor is a bigger repair than the opener install was ever going to cost.