I fish from a kayak all the time. I have a cobra explorer, It's just under 12ft. I've had it a little over a year and have added mods over time and outings. I have rod holders a depth finder a place to hold the paddle tackle storage. I feel safe and have not have rolled it yet (knock on wood). Although I do plan on buying the real deal the yak has it's advantages, storage, easy to maintain, if you know of any larger farm ponds that's when I've had the most fun. Mine was $750 new, I've put in about another $400 with all the add ons, my depth finder was a littler over the top for what I need but is sure is cool having one. I bet you can find a used one already rigged in your budget or not far .
Have fun and good luck.