WENTZEL MASONRY

We received a proposal for an outdoor fireplace. Prior to starting, we made a change that raised it to $5000; unfortunately we didn't get this portion in writing. 3 days into the project, when we have a 6 ft high cinder block wall in our backyard, he tells is it's going to be another $2000; he subsequently added another $500...& basically said he wouldn't finish for less than that. He fully admitted to my wife & I that it was a BIG mistake on his part, but still insisted we pay for that. He also admitted to knowing numbers weren't adding up 2 days prior to bringing it to our attention, when the project still could've been changed to everyone's liking. If he would've given us an accurate quote, we could've done something to bring the cost down, such as changing the location of the fireplace or taking the wood storage bins on the side off. However, by the time he brought it to our attention, we were left w/out that opportunity. I also attempted to just hire his laborers, because it wasn't their fault he screwed up; plus then I could make sure I knew where every dime was going & he wasn't up charging me for anything. He claimed his guys said they wouldn't do it but who's to know if he threatened them w/no more work if they did it or if he even asked them at all. Here's what makes it look worse: he admitted he hadn't worked in a couple months, so really needed the work. Looking at it from our view, he really needed work, underbid us to get the job, got the project to a point of no return, then told us we owed him more money.