If your were to assemble a vintage system ?

@filipedine You're right, extensive service is needed before equipment of this age will perform as intended.  But not quite this extensive. Certainly all electrolytic capacitors in the amp and power supply stages.  Some small signal transistors such as the differentials in Pioneer and Marantz degrade from heat more than age.  In certain makes and model, we have seen resistors degrade.  Non polar capacitors typically need not be replaced.  Some exceptions are the early Sprague "bumble bees" in tube gear.  Operating tube gear with failing capacitors can lead to very bad things.  

It has not been our experience that power transistors need to be replaced, unless there was a catastrophic failure.  A "blown" channel.  Same for power resistors.  Although some diodes are replaced, many can be retained.  Failure of power rectifiers for example is pretty rare, and these do not normally need replacement. As for fuses, they do not normally need replacement.  A blown or damaged fuse is however a potential sign of serious trouble.  Fuses do NOT normally fail.  Replacing and powering up in some cases can cause irreparable damage.  

If you are buying vintage gear, it's a safer bet to get a piece of equipment that has already been through a restoration process by an experienced technician, than to buy an unserviced piece.  Otherwise, buy with the idea that hundreds of dollars of work could be in your very near future.  

I’m actually doing that right now. I’ve been a Hafler fan for years. I’ve got a mint XL-280 fresh from tuneup from ‘85. I finally found a Hafler 945 preamp that’s in transit to my home ( mom still has my SE100 preamp). I’m just completing my restore of a beautiful pair of KEF Reference 104/2 in Cherry today. I’ve replaced the internal wiring with Kimber, rebuilt the T33 tweeters, new center surrounds. I’ll put my old Denon DVD900 back in service. Speakers wired up with 10 gauge wire, PBJ interconnects. At 4 ohm, the Hafler puts out 200 watts…more than enough for playtime. 
The KEF $350 plus $75 for parts
The Hafler 945.    $250
Denon DVD-900 owned
Hafler xl-280 owned
Cables owned

Should be a lovely two channel listen. 

@bluemoodriver
There is nothing rude or annoying about calling out terrible sounding gear. If anyone is annoying it's you with the "all amps sound the same" mantra while beating your bare chest.

Give THAT a rest, please........

When I started college (1971) my parents offered to buy me a new (to me) car. Had a '64 VW that was good enough for me so, I inquired about a 'new' stereo system. Reluctantly agreed....
McIntosh MAC1700 (who needs AM?)    $600
JBL L-100s    $550
Pioneer PL-A25 w/ Shure M91E?  Pretty sure both were less than $350 together. Of course these were 1971 prices but came in under $1500. For nostalgic purposes, I still have this system today. Put way more into them since. Lived in an old house (by Phoenix standards) built in the 20's or 30's. Wooden floor, 12" thick adobe walls and a 12' ceiling. It would really rock that place.

A Sherwood S8900A receiver, an Elac 770H Miracord turntable with an ADC XLM cartridge, a pair of Wharfdale Rosedale speakers.  I owned them all at one time but not in the same system.