Stressed Contractor

My cousin and the plumber I had to hire kept pointing out issues and I kept asking the contractor questions until the contractor couldn’t take it anymore. He said, he felt stressed and he had too many bosses, even though I was the only person contacting him. So, he quit. He pulled his men off of the site that day. We agreed he would send me receipts for the work he had done, and he would refund the rest.