I had less than ideal relationships doing warranty.
I've done warranty work for Martin, Gibson, Fender, Taylor, PRS, Collings, Ovation, Deering, Alvarez, Yamaha, Washburn, Guild, others, and all their subsidiaries - not many I haven't performed work for.
I'm now very proud and happy that I am an official warranty repair center for No-one!
As an official recognized warranty repair center, you are generally paying for an official endorsement. My rates are set at $80/hr. Considering (with no attempt at modesty
) that there are two or perhaps three other shops within a hundred mile radius that can provide the level of service I do, and I'm not charging more than a decent auto shop or plumber in my area, I think that's quite reasonable. Gibson and Fender pay a little bit over half of that rate. Martin pays set fees per job, which can end up ranging from fair, to downright insulting when labor hours are calculated. In the end though it can balance out. I charge $160 for a bridge reglue, and Martin would pay $30 at the time I was doing it. But then there would be set up, adjust action, intonation, perhaps a few loose fret ends, pickguard work, plus some non-warranty repairs in parallel that would balance it out. Still not making retail prices, but it would become more palatable.
There are positives to offering warranty work. First is the advertising and endorsement. You don't generally make much or even any profit on warranty work, but it brings people in the door, who then may buy other products and services. Second, it's just a good customer service feature. In general though, you'll break even at best.
Not all companies are that bad. Taylor is excellent, and they generally would pay me the same amount that I would bill the customer, and in good time. Surprisingly enough, Ovation and Yamaha aren't that bad. Smaller companies that deal warranty work on a more case-by-case basis like Collings or Santa Cruz can be quite good as well. Cheaper instruments like Saga stuff will generally just be returned and replaced. For the big companies that you'd see most of the work from like Martin/Gibson/Fender can pay average, and usually within a decent time from billing. It's still a bit of a pain in my opinion though.
Now you don't necessarily have to do good or even decent work to be a warranty center though. If you are connected with a dealer, can show some kind of CV or certificate, along with your insurance policies, many companies will sign you on if service is lacking in your area. I have one store near me that absolutely butchers anything that comes through their doors, yet they are a warranty center for many. I've even had several instances where customers have come to me and paid full price to undo and redo work that had been done there under warranty. I am always sure to inform customers when I feel their work may qualify for warranty service, and will refer them to the nearest shop that I personally feel is qualified to do the work well, but most end up choosing to trust their instruments with me even if it means having to pay.
If you have a client base and don't need the warranty endorsement to bring them it, I wouldn't bother with it. If you need to do some warranty to maintain a relationship with a music store (another thing I'm glad not to be doing anymore), then it may be worth looking in to. Taylor is good. Gibson/Fender/Martin, so-so. It's all a pain when compared to simply billing the customer, and you will always make less per job than normal. Still, it can bring people in the door, and it's a good customer service, but I'm glad not to be dealing with it anymore.
Best thing to do is just call whatever number you can find online for each company. They'll be able to redirect you to the right department. That department will send you some paperwork, which you can fill out to give you the privilege of filling out more paperwork, which will allow you to wait some weeks or months for a check that may or may not cover your costs.
Just call each company, they'll get you the info you need, and you can probably weigh the options and make your decisions from there.