These guys botched the carpet install at my house. I told them to either redo the carpet or eat the cost because I'd have to replace it eventually anyway. They disappeared for four months, I moved on with my life, then their legal rep showed up at my house on a Sunday afternoon with the 'invoice', demanding I pay.
I showed him the carpet, he agreed that they wouldn't charge me and that I could remove it and return it at my convenience. Then they tried to charge my credit card anyway without telling me, which I had lost the month before and had to get a new one. Then they tried to sue me in small claims court, where we eventually settled, just because at this point I wanted them gone and out of my hair.