i paid,problem not solved and no refund,Winmac ser

I towed my car to Winmac BMW Specialists workshop on the way 8th of June 2015 after a very bad experience of having clueless mechanic work on my car,i explained to John ,the owner my experience,what the previous guy was working on and what i had to buy,he found a cracked crank,mini paid R9000 depositmanaged to get it for me,took the head to engeneering ,finally after a month after that i was told that i can take it,it's ready paid them the remaining R3500,it was smoking very bad from the on set and didn't have power at at all,which i made them aware of,they told me to drive it for a while,but i decided to bring back to them after 3 day cause the smoke was worse,he suggested ihe gets an import engine for me,i agreed,i went there about twice to the check for about4 months as there was no feedback on their side,everyone i was there he told lots of stories that didn't make sense,finally when i went to the workshop on the workshop14th October i found them working on my old engine cause the new engines were wrong,now it's going to cost me an additional R80000,which i refused to pay as it was too much for a return job,the day John took my car out the street stripped,R3000.refun