It sucks man but it really isnt your fault so dont sweat it. Ive been in a similar situation as you only with a car. It was a 91 with 230k miles when i sold it. About 6 months later the water pump let go, then it had a vacuum leak and the gas tank had a rust hole in it. New owner bitched to my girlfriend about it and tried to tell her i sold a known busted ass car (the only problem i ever had with the car was the engine cradle cracking in half, but was replaced)