js appliance repair service

I called JS Appliance Repair Service to repair my LG Washing machine. They came out and gave me a written estimate of $400+ to replace the board., which they would have to order. He said it might be better to buy a new machine instead of putting that much money into this machine. My grandson said he could easily replace the board so I ordered one, for $162. My grandson installed it and the machine was doing the exact same thing. My grandson further inspected it and said it was probably a water pump that it needed. So I ordered that for $59, he installed it and the washer it as new. I asked JS Appliance for a refund of my $50 for the service call, which was totally diagnosed wrong and they refused. They said because I fixed it myself and if you read the fine print they would not refund my money. The point is I paid for a service call/diagnosis which was totally diagnosed wrong. Isn't this their business and shouldn't they have given a correct and accurate estimate? For good customer service they should have refunded my $50. Their response was also not very customer friendly stating "because you took it upon yourself to fix, the loss is on you". I am sure that if I had let them fix it they would have charged me for the board and came up with finding an additional problem with the pump after they determined the board was not the problem. I would bet the final bill would have been $600+, due to their inept trouble shooting. Stay away from this company, they are not customer friendly nor are they able to diagnose problems accurately, which is their business.