Bosh Astro Serve - the Plague

Over heated my Volvo S60 2.4 turbo in Oct 2016.. Bisch Astro serve engineered the engine TWICE incorrectly for a non turbo. They have had my car since May 15th 2017 and took 7 months just to order the pistons. In Nov sent a bill for 38k (quote was R23k) above the R20k i had already spent in 2016. When i said i'd only pay the quoted price the turbo 'suddenly went' at a further cost of R18k. They offered to pay 50% of the turbo which i accepted on 16th May. The agreement went to their attorneys where it say for 3,5 weeks and on th 6th June they came back to say the offer was off as i had delayed (what????). I got a loaner car they lent me in Aug 17, unliscenced, uninsured, unroadworthy which died in March.