Cheap is a relative term
My 97 E420 has been significantly less expensive to run in 5+ years than my 89 TE has in 3, only needing a stop light switch, lower control arms, and regular maintenance. However, it now has 118k miles on it and I expect it to start getting pricey soon.
The TE, on the other hand, was purchased with 123k miles on it, and it seems that I bought it when it was at the stage my other car is approaching. That being said, I have put between $6-7k total into it, plus $10k for the car itself. This includes more or less common items such as alternators and water pumps, uncommon items such as a new fuel tank, and completely unnecessary items such as shiney new 17" wheels and tires. It now has 185k miles and is burning a qt of oil every 600 miles or so, so I think a valve job and or head gasket is in its future. After that the car should be right excepting it's non-functioning cruise control.
So to recap an earlier comment, your experience is going to depend on where in the cycle your car falls and the price point you are looking at.
91 300 CE
95 E320 T