I let their bill get up to about $300.00 and then cut them off, my invoices are for work done in Oct of last year. I cut them off because the abstractor who does Suffolk county for me said that they owed her something like 18K, she got them to pay it down to $6,000.00 and have not paid her the balance, she also is no longer doing their work and is about to turn them over to a collection agency.
I spoke with the owner in January and he promised me payment within a month, I have yet to recieve it.
When I bring on a new client I never allow their bills to go above the $300 mark, I cut them off. Thats my advice to you, turn it over to a collection agency, contact Dunn and Bradstreet and get it put on their company credit and quit doing their work.
The other thing that I have done which has been successful (and I have never not been paid) is gotten mainly title companies and settlement companies as clients. I have found that they are willing to pay for quality work and they pay fast.