Yearly cost in maintenance 1998 e300td
 

I just bought a 1998 Mercedes E300 Turbo Diesel with 66,000 miles on it. I was naive in thinking that I would have 500,000 miles of carefree driving. In the first week I've had it, I've had to put $1,200.00 with no end in sight. Right now I"m told I need a drive shaft which should set me back $1,200.00. Once I get the issues resolved with this monster, what can I expect to pay in yearly maintenance costs? Does anyone know?