In 2006 a sub-contractor did some work on my home. The work was shoddy, the crew was rude and I was generally displeased. I talked to the contractor and told him that I was unhappy with the work his sub did and that I considered our contract open for renegotiation. After several months of getting the telephone run-around I stopped trying to get an invoice out of the contractor. I was very clear that I wanted the invoice so that I could take it to attorney and we could begin negotiating my discount. It's been three years and I haven't heard a word, so I'm considering the work to be free. Where do I stand? Can I have a lien placed on my home without ever getting an invoice? Can they charge interest for non-payment?