Quarto e Quartos - Deposit

I was in a Quarto e Quartos room for two months with my partner. The room was not suitable at all for two people, it was so small we could barely move and so hot we could barely sleep,, but that is not the main problem. They do not want to give me my deposit back, claiming the sheets, mattress and duvet are dirty, sending me pictures as a proof were I can barely see anything. I know we washed everything before leaving but even if that stuff was dirty ( again, not true) the expenses would not be as high as my deposit. Plus they claim damages on the kitchen countertop that consist in a tiny tiny scratch, so according to them we have to pay 84€ for that ( I have no idea where they get that amount from). Terrible organisation