I did a small retrofit of an existing system for a general contractor who gave me a verbal description of the work needed. I provided him with a proposal of requested work with a preliminary price of $3,870.00. The initial payment upon completion of the rough stage of work was $2,000.00. After completing the rough work for the remodel of the home, I received a call to come back and repair some broken and deteriorated ducting in other areas of the attic and on another unit within the attic but on the opposite side of the home. This was a verbal agreement which I felt didn't warrant writing a proposal as we were already engaged on the project and the contractor had already compensated me fairly for the initial work. I responded within 72 hours to complete the repairs due to the contractors need to progress on the project. I was next called with minimal notice to return and complete the finish portion of the job but was unable to do the start-up of equipment due to doors missing from the existing furnace which appeared to have been removed and misplaced during construction. After conversation with the general contractor who wanted me to provide temporary blank off of the furnace using cardboard, I determined that it would be a liability issue to do so and asked him if he was acquiring the missing doors or if he wanted me to purchase them. I was told he would track them down and I left the job unfinished. That was on Jan. 22, 2022. I didn't hear from the GC again until February 23, 2022 when he called and told me he needed the return registers installed the next day and the thermostat put on so that he could get inspection. He texted me back and asked if I could pick up registers for the rest of the home as his source for purchasing them would no longer sell to him. I asked him for a list which he provided and I picked up the registers which I was asked to leave on the counter for his workers to install. Again, trusting the GC to be honest and honorable, I picked up the registers without providing a proposal. I had already put a Honeywell digital thermostat on the unit which I contracted work for previously and when I got to the jobsite I was asked to install new Nest thermostats on both units as the stat I put on had been removed. I put on the new stats but was unable to start the units as there was no power to either unit. I plugged in the unit which I had not previously touched before as it was unplugged. I did so just to check the thermostat. After checking the stat I left the unit unplugged as I found it. The other unit still couldn't be started or tested as it still was missing doors. When I asked the GC by text, I was told to please go ahead and acquire the doors which were over $200.00 each. I told the GC that I would order them but there was a 4-6 week lead time to get them. This work was done on Thursday, Feb. 24, 2022. I sent the GC a text to let him know the work was complete and that the painter was still working on site as per his direction. On Saturday, I got a text from the obviously irritated GC asking why there was no power to either of the thermostats. I again told him that the doors were missing but that I had tracked them down to order them but they wouldn't be there for 4-6 weeks per our conversation. Observing that he was irritated about neither of the units being started (even though I hadn't been contracted to do work on the other unit) I responded with a text explaining my desire to keep both of us from assuming unnecessary liability for something being done wrong. I next spoke with him on March 3, 2022 when he asked if I had ordered the doors which I told him I wasn't going to order until I got paid for the other two invoices I had submitted. One invoice was for $1,115.00 for the ducting repairs and additional work on the opposite system. The other invoice was just for reimbursement for the registers purchased $537.00. I next heard from him on March 7, 2022 inquiring about dampers on the retrofitted system which were never discussed prior to that day. In his irritated state he sent a couple of other texts alluding to me not completing the work requested which was not true. I was never given instructions in writing, a blue printed of planned work, or even a list of items to complete. I completed every task as per his verbal directions and when the homeowner was unhappy as they expected a system that was basically new, the fault was all placed on me who never received complete instructions about the required work. I have been a contractor for over 30 years and until the past two years have never had unsatisfied customers. Recently, the degree of work and expectations has forced me to reassess if I even want to continue to contract work. Notwithstanding, I want to be paid for the work I performed as I have out of pocket expenses which I've paid up front.