Seat time seat time seat time.
If you can't sit in it and then paddle it for real on the water 'feedback' and 'sensory perception' then don't buy it. Last thing you want to do when trying to get into kayak fishing is spend a lot of money on a kayak only to learn that you are uncomfortable or that the seat and foot peg arrangement cannot be adjusted to your body's overall frame and type.
Ask around your local area for anyone that has a kayak (regardless of brand and model) and see if you even like it. Your overall budget also needs to account for other required items - a class III PFD and a decent paddle (both of which can be found for $50-100 each) but there are better models of both that can be found at good prices. Good rule of thumb when buying these two items is get the best that you can afford. You'll most likely need straps (ratcheting if possible) but the basic ones will work just fine. If you are car topping the yak, you might need some protective supports to prevent damage to your car if it doesn't have a rack. Go with pool noodles here. Cheap and always available. If you need a seat with better support, you can find options in the $75 range.
Remember - in kayaking and kayak fishing, the goal is always to be safe first, be comforatble and enjoy your time on the water second, try to catch some fish (bonus) third and return to shore to come back and do it again another day.
Regarding the Ascend line of kayaks, I can tell you one thing from firsthand experience - they are H-E-A-V-Y for what you get. There are several options out there under the $500 price point - Perception Sports, Native Redfish, Pompano (West Marine), etc..... Do your homework and don't rush to buy the first one you come across. Keep a close watch on Craigslist as well - lots of people will sell an entire setup that include the PFD, paddle, some other accessories.
Regarding rod holders, never install a rod holder until you have figured out that the kayak is the right one for you. Then and only then do you start to accessorize. When choosing a location for them, take a fishing rod and a jar of vaseline. You place a dab of vaseline on the butt of the rod and practice your turning and reaching motion to see where you can comfortably get to and set the tod butt down to mark your spot. Now get some duct tape and a rod holder and head out on the water with it taped down in place and try it. If it works comfortably and you can still maintain balance, then you are ready to install it.
Good rule of thumb to follow when installing accessories - measure twice, even three or four times - drill once!!! Even though there are plastic welders out there, it is better to try and avoid that if at all possible! When you are ready to talk about mounting accessories, consider looking at the YakAttack line of GearTracs, Mighty Mounts, and other accessories. They are designed by a mechanical engineer who kayak fishes and is a good friend of mine whom I fish with each year.