lost cpap machine

What is the name of your state? pennsylvania my cpap machine was not working, took it to health provider for repair,they gave me a used loaner. about eight months went by and i received a letter stating that my machine was not repairable and they wanted $700 to purchase the loaner or $70 a month rental.retail is$1200 for new unit. i offered them $400 or i wanted my unit returned they said it was destroyed and could not be returned but they would accept $500. if i decide not to purchase at there price what is my obligation(i belive my unit was repairable it had one wire that needed solidered) if i return their unit am i due any compensation for my unit that also cost $1200 dollars thanks for any input jack