Mods which don't harm re-sale

I’m a Mac guy worst thing you can do is a BAD job, best thing you can have DONE is a good job. That being said, when I see a Mac full of yellow caps it just turns me off. I see one rebuilt with quality PIO, and Teflon Russian surplus, I’ll give SOMEONE more for the build.. I look at what was done (the parts) and the quality of their work.. DON’T drill holes in anything.. Just silicone it in place. Especially a Mac.. Some Vintage Mac guys are pretty Picky.

They will even gut an old bumble bee cap and load it with a better aftermarket (yellow LOL) cap and reseal it.. Those are 2-5000.00 rebuilds too.. Time is money.. Mac guys are NUTS.. LOL

Upgraded Tonearms will usually net you dollar for dollar too, sometimes more..

Regards

I think it's buyer dependent. Myself, I never even look at modded equipment, others it depends on the mod and who performed it and others it doesn't matter that much. 

If the equipment is older that upgraded power supply capacitors should be a value added.  Most mods and be removed but overall IMO adding capacitors like copper V-caps, Audio Note resistors, upgrading a volume control should be a good thing.

Richard Modaferri’s mods to McIntosh tuners certainly increase resale value