And someone waited quite a while to get his modded pedal back, there's been a few other the years.
Just to even things up as an electronics repair engineer myself though it can often go the other way. We can get the go ahead to order in parts, repair the product and ring the customer and let him know it's done. And then we wait, and wait, and wait and after 3 months we send a letter stating if they don't pick it up it's gonna be dispossed off.
Generally it should go like this. Customer brings in item knowing it's gonna cost £30 just to be looked out. After a good examination customer should get an exact price for parts and labour. In my experience you can get almost anything in within a week, even direct from China is only 5 days on DHL so there's never really a need for anything to be in repair longer than 2 weeks
Re uncollected repairs, the bain of every servicemans life! There are however some steps you can take to mitigate the PITA.
You don't HAVE to wait 3 months before sending a letter. One month or 30days will do but be sure to display this prominently and frequently in the works premises and have a copy of the details on or with the customer reciept for the goods left.
Deposit: Charge one. ALWAYS! Any contact with a customer is going to cost you time and maybe money. If a punter is not willing to front 20quid he is a timewaster and even a score will not go far these days to cover your time booking(listening the while to the customer droning on) the amp in, cost of the paper/ticket and then the subsequent time spent checking out the kit, search time for a map and all the while racking up is the 'lectric, gas, phone, rates, rent /mortgage and insurance bills. If you are not earning you are always losing money.
If no reponse to phone calls after repair a letter should be sent, I would make it recorded delivery, after the 30days giving the customer one week to collect the goods after which you are free to sell them. But! You must keep meticulous records of said sale and the repair cost because the punter can claim the difference for up to 7 years (I think).
Insurance (on the punter's kit) is funny one too. Even tho' it is on your premises, should anything happen to it, a fire say, the customer has to claim on HIS home insurance! At least I know that this was the case several years ago when a mate in the TV trade had a fire in his workshop.