Purchase advice

By visiting my father and myself, we noticed an R-Class at the Benz dealer. (It’s just about his car, not about mine. I just support him. Taken in front). Anyway, there was an R-Class Bj 2006 in the top condition and equipment. 89,000km on the Tacho. Well, he has now “in love” with the R-Class and would like to use it for private and business purposes. In other words, annual running performance around 70,000km. Since the vehicle has some technical ingredients (e.g. lkt. tailgate, air suspension…….) etc. I wanted to ask what it looks like in terms of reliability. Is this model at Benz level or do you have to expect to see the workshop constantly from the inside over the next 2-3 years??? Would you be grateful for any “reliability” answer…….. The car can also be seen on Moblie.de: http://suchen.mobile.de/…/showDetails.html?… Achso ist der Preis appropriate???? Greetingle.de