Not quite maintenance, but a real help at the right time: Empty out the entire car. The glovebox, the trunk, move the seats, etc, etc.
Remove every last thing. Inspect and clean up the spare tire. Permanently assign to the garage what needn't be in the car, just near to it on occasion. Update maps, ownership papers, whatnot.
Start a first aid kit, new fire extinguisher (secure it!), breakdown kit with some spares, light tools, blanket/water/food. Some rolled change; a few 20's. You know what I mean.
And make a list of what ought to be done that hasn't been. Not to worry about when, just to have it written and in the car . . . .