First, I say the following paragraph to everyone asking about jointers. Just in case
Be sure you understand the role of a jointer. It is made to give you your first true (straight) reference surface. Then it uses that surface to give you a second surface at some angle to that face (usually perpendicular). That's it. It won't thickness very well. If you try to thickness with a jointer, you'll probably get a wedge instead of a rectangle. This is because jointers don't make faces parallel. They reference on the outfeed table the freshly cut surface. To get parallel, you'd have to reference an opposing face. That's what planers are for.
If you already knew all that, no offense meant. Jointers are a commonly misunderstood tool.
Anyway! When choosing a jointer, big and heavy are the best bets. Big is a two-part deal. Heavy means cast iron. I wouldn't suggest you settle on anything less than cast iron for at least your beds. There are some out there that use aluminum for the beds and the fence. While aluminum won't rust, it will scratch. I've heard many folks complain about their benchtop delta scratching under even the softest of boards. If it'll wear that easy, how can you trust it's surface? Plus, aluminum is pretty lightweight. Not alot of vibration dampening going on, there. Really try to find cast iron for at least the beds. Craftsman makes a decent 6 1/8" benchtop jointer that is ALL cast iron, including its base. Weighs a TON. I had one for a coupld years. My biggest problem? It was too short. I couldn't joint anything longer than about 3-4 feet with much accuracy. Never did I find it lacking, it just wasn't cut out for what I wanted to do.
Width and length are both important. I'd say length is most important, but width can be a factor, too. 6" width is most common. I have an 8" Grizzly now, but i'm not sure i've ever used all 8" at once. 6" usually fits for almost everyone out there. Length is your big thing here.
The length of the beds (infeed and outfeed tables) will determine the longest board you can accurately straighten. The general rule is usually about twice the length of the beds. So if you get a benchtop jointer with only 23" of bed, the longest board it'd handle accurately is about 46" and that might actually be pushing it. Some guys setup auxiliary infeed and outfeed tables and claim good results. I've never seen this work myself. The auxiliary tables need to be DEAD flat and DEAD coplanar to the factory tables of the jointer to be effective. I'm sure with enough effort it could be done. I just never seen it
For your $200 budget, if you live anywhere near a good sized city, you can probably find a good deal on a used 6" delta or jet. It might take some looking, but they're out there. These are the sweet spot jointers for most of the hobbyists i've seen. Just about everyone has a 6" freestanding delta or jet or harbor freight or grizzly or ... etc etc etc. I see used ones on my local craigslist.com site for around 150-250 at least once or twice a week. If you live near a city that has a craigslist.com site, I'd strongly suggest going the used route. For the kind of money you're looking to spend, you should be able to find a very nice 6" jointer with at least 42-44" long cast iron beds and a stand. Maybe even a spare set of blades!
I didn't go into all the other options jointers come with like spiral cutter heads, parallelogram vs dovetailed ways and all those things. I don't normally, because most hobbyists that i've found have no real need for these features. It's no accident that these things are usually found on much more expensive machines. If you had $2000 to spend on a jointer, then sure, we can talk features
Good luck in your search! I hope you find the right tool for you