I had my oil pressure light on and my.mechanic without checking oil pressure said it was a broken switch and fixed it.  My turbo began to make a noise.  Mechanic wasn't well so I went to another who said turbo had gone.  But after keeping it for two days was too busy to fix it.  He said since I'd only had turbo less than 2 years there was underlying fault.  He told me it was OK to drive.  I drove home 6 miles and stalled then it would not start.  AA guy couldn't even jump lead start it.  It was totally unresponsive.  Have I totalled the engine?  I'm not working single mum and my son needs driven around.  I'm stuffed without it so am terrified it's useless now.  I bought it with money my.mum left me for 11k back in 2016.  She left us 20k each so I very not even any money to fix it.  I've done a go fund me.  Can anyone advise how much I'll need.  Thankyou very much.  

New turbo will cost you around £900 to fix. It will need a diagnostic check carried out. Unfortunately with running a premium brand car such as Audi, bmw or Mercedes no matter how old the cars get the repair bills still stay the same due to the cost of parts.