Apartment destroyed in 3 year tenancy

I was paying this company alot of money a month to manage my apartment tenancy. The agency never checked the apartment once during this period. The tenant was in my apartment for three years - took a cat in the apartment ( unknow) which then destroyed all the carpets ( cats urine), torn and destroyed a leather 3 piece suite, ripped wall paper in the bedroom by having removed something in the middle of the wall. Melted cooker knobs so oven bacame unuseable. Left the apartment before the checkout date and when the checkout was done ( no itinery was usd). The first time I was maade aware of the tenant leaving my apartment was 8 weeks after the tenant had given notice and someone phoned me to ask if they could release the deposit. This means that no one checked the itinerary at all and I was never made aware of the tenant leaving. I am now in a position where my apartment is unrentable - so losing money also. This agency do not care - just want to take money off you.