It's almost a dice game on buying used DNF audio gear, as it seems there's less options on repair sources to be had.
In many ways, it's like cars; if the part(s) are readily available, the problem easily identifiable...no problem, except perhaps the $'s involved. And one has to decide if it's worth the time, trouble, and cost to pull the trigger on the desired item.
When I read about some of the travails some go through getting an item new enough to be on warranty fixed, I pause....
I've had enough issues on some of the tools we have and use.
I've started to bypass 'brushless' items; they tend to have less torque and overall discernable power, whereas a brushed tools' brushes are an easy fix.
The next item that breaks is generally the trigger, an easy swap.
Fixing a brushless tool involves sending it to a repair site, which will advise spending the $'s on an entirely new tool. The repair, with shipping to & back, and tax, seems to be 50% and up towards a new one.
One learns to get picky and fussy about selecting a potential 'down the road' headache, unless said item is irreplaceable in its' functions and applications.
I'll buy used audio with that in mind, opting for new under the same 'parameters'...
For my DIY speaker 'affliction', I've been lucky that the folks that know of it 'gift' me with cast-offs or the orphans that they've acquired in some fashion.
Even if it's just one (prefer pairs)....I've a list of 'what if ?' things to try on those units of no 'pedigree' and no real future except Salvation Army or the dumpster.
And even the latter may lose their magnets, to become nail & screw sweepers.
One gets tired of having tires on the vehicles repaired, the most annoying being the 'sidewall strikes' which can't be plugged....
