I'm not looking to spend too much, hopefully around $350 or less. All i would use it for is tank and some river fishing. I would need a place for a cooler and my tackle boxes and would probably end up putting a fish finder on it. What would y'all recommend? sit-in kayak? inflatable?

If $350 is your total budget, you're pretty limited because you also need a paddle and PFD. Check out ads on craigslist, this forum, and other kayaking sites. You must factor in your weight and the weight of your gear. The small, inexpensive sit-insides are pretty cramped and don't seem to have much room for easily accessible gear. Inflatables tend to ride high and get blown around by the wind.

Given your budget, I'd suggest saving and buying later, or look for a something like a used Wilderness Systems Pungo, Perception Pescador, Ascend 12T, Feelfree Move, etc., assuming those meet your weight requirements.

You can get an older used kayak in that price range. Nothing fancy. Sit on top is way better IMO.

Alright how about closer to $500 for just the kayak, then what would y'all suggest?

The academy in college station had a Pescador 12 on clearance for 299 this past week. That's dirt cheap! Very good yak. Check your local store to see if they have similar.

I have a ascend FS128T with hull mounted fish finder - not sure what it is worth?