Repair or Replace ???

Vinyl players are more reliable.
Have 4x Technics 1200(DJ use)
1 Empire 698 since 80's and Michell Gyro SE since 2001.
All of them woik like nu.

Meanwhile changed CD-players many times for various reasons and quitting reading or jumping isn't out of that list. After Q-tip wiping and blowing the dust out of mechanizm it worked for a while but than again same story after a few months.

Clean it wipe it, make sure it works than sell it as-is with disclosure. That was my game. Another reason formats are always changing and you want to use the best with corresponding player capable to play specific format.

Out of my record/book/cd/media store shelves with CDs are slowly being depleted as more and more space is needed for vinyl due to the demand.

Kijanki,
Your brother is very lucky. I get them to my store from customers with tough problems such as blown photo-diode which is basically a sensor to position tonearm. That part now is irreplaceable in vast majority of vertical TT. Once it happens the only cure is to replace the tonearm system and lay it horizontally.