In this spirit, I offer my personal observation about the two kinds of Cabriolets on the market. I hope that you will consider my insights if you are in the market, in addition to reading some of the excellent resources available online for prospective buyers.
First and foremost, the E 320 Cabriolet is a mid-90s example of a 124-chassis Mercedes. When you include all variants, there were 2,562,143 units of the mid-level Mercedes manufactured no more recently that 19 years ago. So at this point, any known engineering weaknesses are well documented. Among these are at least two you must consider, starting with a faulty wiring harness and a leaky head gasket. These are known issues that can cost thousands to fix that every Cabriolet owner eventually has to confront, along with issues like leaky roof hydraulics, a faulty throttle body and a bad a/c evaporator.
So among decent, presentable Cabriolets, this creates two kinds—the kind that have had these repairs and the kind that haven't.
These flaws take time and miles to appear, so coveted low-mileage Cabriolets often have these repairs still looming in their future. Thus, the issue becomes whether you want to purchase a low-mileage example with work to be done or one with more miles (75K+) that has already confronted these items.
Here's a perfect example of a handsome '95 Cabriolet that has traveled just 50K from Craigslist in Miami:
Mind you, the ad says nothing about needing a new wiring harness or head gasket, but I'm guessing it needs both. The owner parked it in his garage and hasn't touched it in four years. Condition is noted as "fair." Sounds like it has issues keeping it off the road. Certainly the body looks good. Just to be safe, I would also factor in leaky hydraulics for the roof. Just a guess, but I'd venture to say this car has these repairs in its future. Is this example worth considering for those in the market? Depends on your budget. I know I would consider it if I were in the market today. It looks to be a clean example. I would speak with the owner at length, look at maintenance records, and price it accordingly. Just don't assume you'll immediately get a car that's road-worthy.
The other choice is a car like this with twice as many miles:
One never knows, but if I had to guess, I'd say this car is ready to be driven today. Looks to be straight and undamaged, 113K on the clock, and a price of $8K. If the car is as good as it looks, this seems like a good value. Again, I would consider this car.
To aspiring Cabriolet owners, I say take heart. There may be two paths to choose, but I consider both to be appealing. 50K and 113K aren't a lot of miles for a robust vehicle like this if it's been properly maintained, so it's hard to go wrong here. The issue is what, if any, should be the premium for a low-mileage vehicle when you know major repairs are ahead. Also, what is your tolerance, financially and emotionally, on sorting any issues out.
As a rule, I would advise to buy based on condition, and not mileage (and certainly not by color). Low-mileage is just a lazy way to get a quick read on wear & tear. Yes, a car with fewer miles can be less worn, cosmetically and mechanically. Then again, in a market where cars are leased and then simply discarded, mileage says less about a car these days than ever. With the Cabriolet now entering its third decade, the difference between enthusiast-owned examples and just plain used cars is more obvious than ever based on real issues like rust and not merely the number on the odometer. In fact, among unrestored Pagodas, some of the nicest examples I've seen have 150K or more enthusiast-driven miles on them.
In the final analysis, the best advice for individuals in the market is to buy a Cabriolet that's been loved and to enjoy it. There's a lot of upside in the current market, so aspiring owners would be wise to take a long view towards the benefits of ownership. Buy a good one, drive it, and enjoy it.