depends on how many cakes to take... if ask to take just 1 cake, dun expect them to charge any less, if take more than 30 cakes, also time taken would be longer, so charges increase as well.
since cakes you can't move around, the photographer have to be there to take photos, den depends on the 'layout' of your brochure, you want plain background so that you can PS the pic with other things inside, or you want the pic with other 'accessories'...
Setup wise, i think would need to bring a tent, or you need to at least have a canvas, flashes, depend on the type of cakes, bounce or softbox, etc. btw, cakes can't take heat, so it have to be taken fast & light have to be cool lights, or if using hot strobes, really must kin kah kin chiu (fast leg fast hand) hehe...