my mk5 had 2 headlight burn in 10 years, and no other bulbs that i recall. (my mk4 had bulbs burn if i glance at it wrong
)
we had it for just under 200k km, automatic. and upto that point, replace 2 wheel bearings and 2 axles. both at the front (axles, obviously)
as preventive maintenance, did spark plugs twice, but mechanically very sound. even the shocks were still original.
they were certainly on their way out, but not fully out yet.
at that point, the only thing that was bothering me about the car was sway bar bushing squeaking in winter. little lube and it would go away for a while.
2.5 inline 5s certainly feel like reliable old motor.
your friend's wagon may not be worth full 8k asking, but i would easily think it's worth 5~6k. 4k too little.