While preparing our home for sale, I had asked a local contractor to assist me with redoing the chimney flashing for the wood stove. The labor amounted to 2.5 hours and materials were approximately $125 (1 bundle of shingles, some roofing sealant, roofing nails, ice and water shield). He never provided me an estimate (verbal or written) and did not invoice me prior to our departure from NY. Afterward, he sent me a text telling me the bill was $850.00. I still do not have an itemized invoice to this date. I expected $400.00 - $500.00, as his prices are generally higher than other contractors, but I didn't expect $850.00. I sent him a postal money order via Priority Mail for $450.00 with a letter and he is threatening to speak to the new owners and place a lien on the property. I honestly believe that he is bluffing, however I want to ensure that there is no real recourse here. I paid him an amount which seems to be fair for the time and materials, as my research indicates that this type of repair would run anywhere from $250.00 to $400.00. As I mentioned, he has still not produced a detailed invoice for the $850.00 he's asking for. I appreciate any advice you can provide. Thanks in advance for your time.