If you buy a branded/salvaged title Tesla you can't charge it on Tesla's Superchargers. In the past, Tesla said it was for safety reasons (i don't want to be around some junker Tesla charging when it goes nuclear because some weekend mechanic didn't know what he was doing).

But now Tesla will be offering 'Safety Inspections' and allow cars that pass back on the charging network.

This is probably also the first step to having 3rd party repaired battery packs.