Hello Nik,
Welcome to non-lurking status.
If you haven't heard it before, hear it now: buy the best car you can afford.
If you can afford more then the asking price of this car, that is my suggestion. There are plenty of 230SL, 250SL and 280SL's around in equal or better condition--perhaps not in your backyard, but they are available.
There are quite a few cars out there that have incorrect or missing trim; so your missing chrome isn't alarming. Also, some people over the years actually removed chrome because they didn't like it. Some don't like whitewall tires either. If you want to bring it back to "as delivered" then you'd have to find the trim pieces--not impossible, but a task, and one that will cost something.
Sloppy steering could be any number of things from bad tires to a bad steering box, loose fittings in the suspension, or old or bad rubber. Not unexpected at 39 years/102K miles unless somebody was on top of things at all times. They rarely are or we'd never see cars degrade like this.
Smoky? Round up a group of 113's and you'll see a lot of smoke. Best to do a compression at minimum, leakdown at maximum test in your inspection to determine the condition of the engine. It probably has not been rebuilt, but at 102K, may be due for a rebuild in your lifetime.
Alex Dearborn is very well known and I can almost guarantee you will be alarmed at the comments. There's a lot to do on this car just from the photos, and you'll hear about all of that. You'll also hear about the things we can't see--which might be more.
Take Rodd's comments to heart and determine what your needs and goals are. Take Kevin's advice on buying the best you can afford. While there is a LOT wrong with this car, there's plenty right too--making it an ideal candidate for restoration. Restoration will cost more money then you think (trust me on this) particularly if you hire it out. Total restorations on cars like this usually occurs when someone wants to do it themselves as a fun or learning experience or if there is some sentimental reason. Leave your checkbook at home if you don't fit into these categories...
On another note, I've been seeing, hearing and watching a lot of 113's being offered for sale recently, some changing hands, and peculiarly, the majority of them are 230SL's. There are 280's out there, too--you just have to look.
I agree with Rodd on the value, just based on what we know now.
Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored