Should this contractor's bid still be given a fair consideration?

[Chrystal T.]

#contractors_are_shady

A contractor who was working with my architect to complete blueprints for the county's plan check always took his time to provide necessary information, and refused to give me an itemized bid because he is "just a general contractor" and thus cannot afford the time/resources into providing an itemized bid because it runs the risk of me finding specific tradespeople for tasks he subcontracts and marks up. Because he thought he had the job for sure, he would always throw out random numbers - and they would always change for the same task. So I sought other opinions, and when he found out, he gave a bid  lower than what the others estimated. 

As sketchy as it sounds, I was considering going with him because I know he works on a smaller scale which might justify the price difference. But after the architect sent out the final plans this morning, he - who has always been slow to respond to emails - texted me immediately with the following message, "based off the blueprints, I'm estimating construction costs to be $45k because windows are an additional 8500. Once I get a working set of plans I can give you a proper bid, this is why I said i should be in the loop"

That's a 40% increase from his original bid, and none of the other contractors' itemized bids for windows came anywhere near 8500. And when he was kept in the loop, he wasn't performing, so now that he knows his job is threatened, he is complaining about being out of the loop? What allows him to feel entitled to do so? In fact, his delayed responses caused a lot of delay in obtaining the building permit - plans were supposed to be submitted prior to the holidays but because he was lagging, they didn't get submitted until mid-January. 

I didn't respond to his last text, and he had the courage to proceed and say "If you're gonna want me involved in this project I'm going to need to know I am starting to get very busy"... Excuse me? This project was supposed to start four months ago, but he clearly had not been in a rush to lock down the project until now. 

Should he still have a shot at the job?