not willing to help at all

purchased a used 2011 audi a3, on delivery of the vehicle driving the car home i felt that there was a vibration coming from the rear of the car, as i work at a dealership myself i asked the tyre specialist to inspect the rear tyres, he then reported to me that the rear tyres are completely worn on the inside of the wheel. i then tried to start the car to move the vehicle from the lift and the battery was flat and car was battling to start. i then took the car into the workshop and tested the battery and the battery had 2 dead cells. they agreed to replace the battery and said it will be brought to me and fitted the following week. 10 days later still no battery and car did not want to start. i then phoned and then only did the battery leave the dealership to be fitted. new battery fitted the car starts and now there is a misfire, on inspection the spark plugs needed to be replaced and the coils were shorted out, causing misfire when it is started. i have had the vehicle looked at by a private mechanic as i do not trust the suzuki technicians who have supposedly already done a 100 point check. the sales manager refuses to contact me after contacting him on the 25-26/01/2016.