Couple of other things to consider, guy. jjdebird makes a good point about what flat water bodies can do for you. For one thing, I always tell new folks starting out to consider where you live and make the most of it. If you're close to flat water, that's where you live and are going to stay for a while, adapt and find some excitement on flat water. It has some real potential for your health. I, for example, live where there is only one class III place in the state. So I gravitated towards fitness endurance paddling for speed and racing on flat water. Those of us that have paddled racing kayaks or surf ski's can attest to the fun that is. Slalom kayak sprinting on the flats will carve your body like nothing and you always come back in a better place than when you left. Another thing about that is, at least in Florida, flat water can become rough water with wind wave swell that is QUITE the adrenaline rush (and for weeks now here in Florida anyway has). It's called rough water kayaking and it may be coming to a water body near you! It sort of puts you onto a gradual self-taught regimen too. Get yourself a boat and practice on the flats, then when you hear the small craft advisories--down the road mind you--get out and play near-shore. Then step it up and up and up and up....
Instruction should be cheaper than what you quote, but instruction is always a good thing if you can get it. I was self-taught. Now I ride 30-40 knot wind swell wave trains, so it can be done. I have no death wish, mind you, and I mitigate my risks in every way possible (best gear including appropriate boat). So it can be done and you do it over time. Then take those trips to nearby whitewater too.
Best advice is to make kayaking an actual part of your life, in my opinion. I've encouraged people I have tried to help get started to get a boat that meets as many of their goals as possible, that is light weight and maintenance-free enough that they will find themselves doing it often. If you end up being the kind of boater that has to put a lot of effort into loading up and driving far you might be missing out on a lot of fun (like the once a month boater where it's a big production). Get yourself into a situation where you can just sling your boat over your shoulder and get into the water in like 30 minutes. If that's a flat water endurance run then so be it.
For what it's worth. (That'll be 2 cents please.)