Hey mate there's a lot of questions to ask when picking a kayak.
New/second hand
What type of fishing( off shore , fresh , estauries ,creeks/rivers)
The length of the kayak. Longer = faster shorter = slower and more maneuverable
Wider = more stable skinnier = faster
From what I read you are looking for something in the fresh I presume it's for bassing?
I would be looking for something on the smaller side so I can move around the snags rocks fallen trees and structure easier.
The Viking nemo goes for about 700 $
Weighs 20kg 3.2m long 0.79 wide
Viking opal is a sit inside. About 800$
3 m long 21 kg and 0.8m wide
Ocean kayak Frenzy about 600
2.74m long 0.76 wide 19.5 kg.
These are the small kayaks which are listed in my kayak manual book.
If you want a pedal kayak your best option would be the hobie mirage sport which is the smallest of the pedaling kayaks but very pricey compared to a non ppedal kayak.
Keep an eye out for second hand kayaks you could snatch up a bargain.
As for the soft roof racks I hav no experience more do I know anyone who owns a kayak who uses one your best option would be to get a set of roof racks
Alan