Long time ago I bought home made computer, it was freezing all the time. Took it to a local store, his diagnosis was the computer was not mounted properly and the board had some circuit issue, the seller told the judge that if surge protector was not used , the guarantee is voided and the seller prevailed .
Lost half month of paycheck on desktop and another 35 court fees.
Do you have law school around , some of them may provide you legal advise. Check it out.