Welcome to the forum.
Don’t look for items just in your LHS or the modeling section of WalMart, Hobby Lobby etc. Check out the crafts section of those stores or visit a crafts store. You can find a lot of things (razor knifes, paint brushes) that cost a lot less. I buy my body putty and enamel reducer at the local auto supply store. Initial price is high but they last a long time (body putty costs about 12 bucks a tube but last about 5 years and a gallon of reducer costs 14 bucks but will last 2 to three years).
Now that spring is here, check out the yard sales and flea markets that start about this time of year. You’ll be amazed at the amount of models, accessories, tools and supplies that you can find for pennies on the dollar. Check out Ebay (although the prices there are rising - think that there a lot of LHS owners who have discovered they can make more money there than they can in their shop)
When you buy kits, look for older kits. There are still lot of old Revell, Heller, Airfix, Monogram, Italrei and Hasegawa kits out there for about 1/3 to 1/2 the price of the current item. Granted they may not be as nice as the newest release but are just a satisfiying when completed. You just have to put a little more effort into them. Besides which none of the current top manufacturers have seen fit to release a J2F6, a BV 141, an FW 200, a BF 108, a Do 217E or many others in 1/72 scale (although some of the Eastern European mfgs seem to be taking up the slack here - for a price)
Just “think outside the box” and you’ll be able to do ok