Welcome to the forum. As some of our owners have suggested looking into a used cat, from scrap yard or parts for one. We have a lot of owners in Texas who might be local to your location, who might help you... install it one day for 6 adult beverages? Modest in price compared to what the dealer would charge or local shop.
I would look into the wheel rubbing when turning. Might be serious, maybe not. Loose wheel well liners or bent steering rack, until you look or inspect it with a trained eye, while they install your cat? Doors squeak could be just a lube question to the hinges, or they might be pinched and need some " adjustment " and maybe the front fenders too?
Replacing the cat, clearing the codes, check engine light, passing emissions or state inspection to get the car back on the road is one thing, but the " steering issue " could be more of a problem down the road if you will, if something in the rack is bent, and needs replacement before you are able to resume your permagrin status. Safety first and fore most here. Battery first. Tires second. Brakes third maybe second here. Steering/suspension is next up. This car is not cheap to fix, in most cases but you can save money over those outrageous prices the dealer charges. Lot of good owners here that are willing to help. They can point you in the right direction, what to look for, what to avoid like the shady dealer who will try to tell you everything needs replaced $$$ to get your car back to where it should be for you. IF you can find a local Kappa owner who has some free time, their eye and experience could save you some of that green stuff we all like.