Potential problems

considering buying 2003 mercedes benz SL500, has anyone had bad experiences with this car

They’re average to ‘worse than average’ on Consumer Reports. If you buy it expecting maintenance costs that go with an $80k car with average reliability, that’s ok. Don’t expect Lexus-type reliability.

The most common ‘problem’ with these is a lack of maintenance. Only consider one that has a fully documented (that you have inspected) maintenance history. Often they’re on their 3rd or 4th owner, and are neglected.

the one that I’m looking at has had only 1 owner and has all maintenance records, appears to be in excellent condition and the price seems very good. Also, the owner says I can take it to the local mercedes dealer and have it looked at. It does have recent inspection. I do have 2004 lexus LS430 and your right, it is very good on maintenance. Under these conditions I just described do you think this is a safe bet

Sure sounds reasonable, given a clean bill of health from the dealer (have them review the maintenance history, too). Of course, any 7-year-old car (especially one as complex as a top-of-the-line MB) can have unexpected problems.

You might post your question on a MB SL forum, I bet you’ll get several answers from owners of that exact model.

how would I find MB SL forum

Google ‘Mercedes SL forum’. That SL is often referred to by its platform label, R230.

MSN Autos says that there is an occasional problem with the mass air flow sensor. They estimate the repair cost at $300. They give it their highest reliability rating. If it has been well maintained, you should get many years of enjoyment.