S-Class shopping, please advise

I would like to thank everyone in advance for your help and suggestions!

I am looking to buy a 97-99 S-500 or possibly a 00 S430. This will be my first MB and the one car I have wanted since I was old enough to know what it was. That said, I like to be as educated as possible before I "jump" into it, especially when it is a car purchase. My questions for you are:

What problem areas should I be concerned about?

When I find one I like, are there any characteristics I should look for that would indicate a possible problem?

What routine maintenance is suggested/needed at what miles?

I have been told before that I need to make sure it blows cold air because the condenser (I think) is known to break down. Being that it is located behind the dash, the dash must be removed for repairs and typically costs $3,000 - $3,500. It is problems like that I would like to be aware so I can be prepared should such a situation arise. Again, thank you so much for your help!

[royaiii]

I would buy the Mercedes that still has the factory warranty not the starmark warranty (have heard they say everything is covered come time for repair) meaning the new design is a better choice. I have a 99 S420 and I had at least $8,000 done for me by through the factory warranty. I would only buy the 99 (not other years) S500 because that is the last year and they fixed the expensive AC evaporator problem. I have a 2001 S600 and it is a better choice for everyday driving but I always take the S420 on long trips. If you buy the S500, I would highly recommend you take it to a dealer for a complete estimate as one anomally could set you back alot. Repair of both of these chassis, requires a highly proficient technician because of the complex electrical and vaccum systems involved.

Thanks for your help. I searched "W140 Maintenance" and found much needed information. I am finding this decision difficult as my research has shown Maintenance costs much higher than my expectations. To my surprise, I've noticed many complaints about the W140 chassis's reliability. On the same token, most complaints were followed up with praises and admiration for their cars and feel the extra output is well worth it. Right now, I am thinking of shying away from the W140 for a comparable car that is more reliable. Reason being:

I am a Case Manager for Anthem BCBS out in the field. I spend most of my work time driving to hospitals, private homes, etc to verify personal injury claims. I can't afford to be stranded on the side of the road or have my car in the shop all the time.

Is there anyone else in my situation that has a W140? If so, what has your experience been with the car?

[savagetom]

I bought a 95 S320 with 50,000 miles on it and it now has 104,000. It hasn't missed a beat. I should mention that the car had all the standard problems fixed by the previous owner under warranty. These included the head gasket, the timing chain cover, close assist pump, wiring harness, and blower regulator. I wouldn't buy a mid 90's version if these items weren't adressed.

I had thought of trying to find one like yours, where all work had been done before I purchased it. I appreciate it, your input is definately helpful.