heating and ac repair on ranger

I thought we'd try this guy after moving close to his place. we got a flier in the area. My regular mechanic quoted me 300 and Maddox was 325, but it was close and I figured it would be nice to have a mechanic nearby. I told him my son had been unemployed for several months and we needed to keep costs down in repairing his truck since he was selling it. He texted that the truck was ready the next day with a $446 bill!! I told him we did not have that and it was more than the estimate. He just kept saying its an "estimate" which means it can change and he found something else that had to be done to "get it right". In 25 years of having my cars fixed, never has a shop, individual or dealership gone ahead and repaired something else without calling for an approval of the price change over the estimate. NEVER. he would not back down. I called my church for help for the extra money,, but maddox would not take a credit card from the church and said cash only. So my church could not help without a paper trail for their records. He really put me in a bind and if that was not enough IT"S NOT EVEN FIXED right. When we drove off, we began to hear a rattle in the engine that was not there before but we do not trust the guy to take it back to him. DON"T GO here, find someone else with some good reviews.