That's a nice looking car. Would be nice to know if the service records they show can validate the very low mileage (kilometers) shown on the dash. They took lots of good pics.
You're right, nobody wants to be stuck with a money pit! Rust is the #1 concern, as well as #2, # 3, and #4 concern! It's the most expensive thing do deal with and can be hard to find at first. This is the most important thing your inspector should know how to look for. Then, all the mechanicals.
There's a lot of nice pics of that car, looks great at first glance. The engine bay should be body color and firewall pad is missing, so who ever did the painting was not trying to go "concourse" by any means. I wonder if they took off all the trim and lights to do the paint job. I wonder what the original color was. There are quite a lot of original, correct things shown in the pictures. I like the chrome strip that would be below a narrow Euro rear license plate. I wish I had that radio! It doesn't have a locking gas cap, but reproductions don't cost much. Panel gaps look good. You can't get the brown door sill rubber mats anymore. I wonder if this has the original brown rubber floor mats under those carpeted floor mats. The engine has a fan shroud, I think that is unusual for a 230SL. It has a tool kit, but would be nice to see all the tools out. A correct original set is worth crazy money, so they probably replaced any valuable tools with basic ones. This is a European model similar to my 230SL, and actually was made very close to the same time! That car's VIN ends in 18201 and mine ends in 18381.
Do you already have a good mechanic lined up to use? I'm sure there will be things you want fixed within the first few months of ownership. If you're handy at all, you can learn to do basic maintenance yourself, which gets you to know your car more intimately.
Along with the link to our site I posted above, take a look here for what a good car (original, and restored to original specs) looks like.
https://www.motoringinvestments.com/mercedes-280sl-w113-buyers-guide/https://www.motoringinvestments.com/restored-cars/If you don't snap this one up, then I strongly recommend you go drive a few Pagodas that you find for sale near you. It may influence what your priorities are with regards to what things are good or bad with any car you are considering for purchase.