This is a topic that surfaces now and then. You have two sides.
Side A - go to a parts store for a code scanner “free scan” (this is not to be confused with a diagnostic tool) - which really doesn’t do much of anything on today’s later model vehicles .
Side B - Have a REAL diagnostic tool that also does code resetting among the many other system tests and diagnostics one NEEDS to solve problems on today’s vehicles without throwing unnecessary parts at it.
Autel with the scope and TPMS tool is abit more than $3k and when I checked with O’reily next to my store, they were willing to give the DMS a better price break than what they show online plus they will extend their tech service and warranty. Unlike Amazon - their Tech service is a local tech rep that would come out the the Makerspace for training etc. (buying local sometimes may cost a bit more but the service after the sale often more than makes up for it).
This will most likely require a yearly software license - another expense to budget for.
There are many other more expensive options
Snap on - not sure what their latest brick is called - modus or solus or ?
Plus the Really expensive brand specific ones like the Mercedes Star tool.
Later cars have systems now that require more than just a “code reader” to do tasks that used to be basic or routine.
Try changing struts/shocks on a car equipped with a"lane change warning" system without a diagnostic tool to reset / disable the system and see what happens…
How about SAS?
CVT’s (those rubber band like transmissions)
Electric parking brake - you later Nissan and Audi/VW folks (for a start)
too much to list to not justify the tool.
The trick will be …how to keep the tool from walking away from the dms?