In the "old" days...
I once met a guy in his 80's who had owned a small used car lot back in the 50's and 60's.
He told me how they used to "recondition" their used cars back then.
High miles were never a problem in those days. A traveling "clock man" would call on all of the used car lots on a weekly basis and for 10.00 the odometers would read whatever the lot wanted.
" We ALL did that back then!" I was told.
They also had a traveling "radio man" back in the days of vacuum tubes and vibrators. For 10.00 the guy would "fix" the radio so it would work. This may involve replacing a tube or two with a used tube but when he left, the radios would be working. For how long. who knew?
The "battery man" would come around and for very little money, he would install a "rebuilt" battery.
Batteries were rebuilt by draining out the old acid and debris, beating on the bottom of the battery with a rubber mallet to dislodge the crud that was causing the plates to short out. Buff up the battery case on a buffing wheel, install some shiny new caps and the battery was ready to go...at least for awhile.
Take off the oil filter, clean it up with solvent, put in some fresh reclaimed motor oil, replace the two spark plugs that were causing the engine to miss and the "reconditioning" was complete!
Tires were often regrooved or replaced with a set of recaps!
Sawdust was great for quieting down a noisy differential of manual transmission!
This old guy just couldn't understand why we still don't do these things!