For an 8inch cake you can get ingredients for a fiver and it takes all of an hour to make and bake
Ha, ha, ha, ha - that's a joke, right?
You can really get all the ingredients for an 8" cake to serve 25 for a fiver? Have you included butter, jam, sponge flour, sugar, eggs, icing sugar, professional quality sugarpaste, electricity, cake board, cake box, ribbon, food colourings, baking parchment, specialist gums, egg white substitute, cling film, contribution towards equipment (mixer, bowls, tins, cutters, sugarpaste rolling pin, piping nozzles and a myriad of other things).
And in an hour you can shop for ingredients, make, bake, cool, ice, and decorate the cake, plus time spent taking the order, discussing the order/emailing the customer, cleaning, washing up, checking payments, accounting, marketing and anything else I've forgotten.
Because if you can do all that in an hour, for a cost of £5, you should go into business making bespoke cakes - you'll make a fortune!