Which items do you think will be the most expensive? We've had to throw together stuff for our cats before (surprise kittens, then later dominance issue so we needed to make more things for each cat to get away from each other) so there are ways to get cat things for cheap/free
You can put the food bag in a sterilite tub you have at home temporarily or some other container you already have. Same type of thing with a litter box, for a few days we had to use a small...I don't even know what it was, it was like a bucket, but sort of litter box shaped, but we just had to wrap it in trashbags and use litter in there when we were having some serious cat aggression issues and had to keep one of our kitties on the other side of the house. It was just something we already had available and so we were able to use it immediately. Litter is something you can't really skimp on, same with food, but then things like the food bowl you still can. Any bowl really would work. If you were to use like a cheap plastic one you would need to wash it more often. I would maybe start out with just the brush for now as far as grooming supplies and just brush him often until you can afford the others. Then if you can find the cheap carrier, go for it!
Check craigslist for supplies as well! But wash them well if you get something from an unknown source.