Are you good with soldering n electrical troubleshooting??
If so, I would recommend getting a vintage integrated or receiver.
Anyway, if you get an already recapped/refurbished unit then no need to worry for another 20-30yrs.
Certain models of late 60s all the way to late 70s from Marantz,Pioneer,Sansui,Yamaha,Luxman,Kenwood are very good value for money and will outperform most of the current entry level/mid level amps. They looks beautiful and well built compared to today's standards.
Another main advantage of these vintage amps are ease of repair and troubleshoot in case of fault as those are made with discrete components which are easily available and cheap. They will always appreciate in value unlike current plastic entry level junk.