Business ProfileforAffordable Engine Exchange

Gave a deposit if $1,800 and was told my vehicle would be completed in 2 weeks.It was almost 2 months before they even touched it.Original price agreed was about $3,400.So after 2 months they perform a diagnostics and tell me that it's gonna cost twice as much,so now it's about $6,500.Since it took them 2 months I had to buy another vehicle so I told them it was expensive and I didn't have the money it would take awhile and I will get back to them when I have the money.They start calling me every 2 days harassing me about when I can give then more money.Keep in mind I've given them $1,800 and I've never known an autoshop that wants the full amount before the work is even finished.So finally because of all the harassment I told them real nicely and respectfully that unfortunately I just don't have the money and I don't feel comfortable giving them more money when they told me the deposit was for parts,so I told them it's fine just tell me what I owe for the work done and I'll come get my vehicle no problem and no hard feelings.The guy gets mad,tells me I owe him now for all kinds of fees that were not in the contract and totals to $2,800.And I was like ok I have no choice,since I paid $1,800 already I'll bring the remaining balance,he says no he wants all $2,800 in cash and THEN he will refund the $1,800.I tell him I don't have that kind of money at the moment he says fine its $35 a day until I pick it up.I owe him about $600-$800 for the work done and they owe me $1,200-$1,000 refund or in parts.Please help,this guy is scamming me and has most likely scammed other people.Thank you