Thankfully this is a very small issue for me, but very disturbing when it happens. First you have to consider if your customer has a point. If they do, make it right to their satisfaction.
If the work was fine and they just don't pay you can do a before/after bill like utilities. If it's late they start paying interest per your contract. Next a letter stating legal fees and property lein costs are going to be added. A letter from your lawyer after that is a good idea. Get legal advice early on the timing for a lien. If you're late, you're out of luck (although a lawyer told me ages ago that if I went back and tightened a screw that would make the timing OK again).
Some people just want a lower price, not to cheat you completely. It might be easier in those cases to take what they offer and don't work for them any more.
In over 20 years I've only filed two liens. One paid and the other went bankrupt, so my lawyer was the only one that got paid. My losses are such a small fraction of 1% that I have people laugh at me for tracking it. In general I work for honest people or I'd get out of the business. I usually get a real bad feeling from the cheaters in the early phone call or bid stage and get away.
Dave
