Plumber did some rough in work on my house in 2019. Did not return. Finished the job myself, meaning I installed my own toilets and sinks. Now he claims I owe him a staggering amount. Out of line. He has piled up a fee from another job on my (finally) an invoice. I requested invoices along the way so I could pay him then too. Nothing. No contract. Now he threatens a lien. What do I do? Thank you.