Just done mine, a U shape galley kitchen. 3m long 3m deep.
Did a lot DIY, ripped out the old kitchen, then discovered the shoddy job previous owner did, a lot hides behind a kitchen!
So I had to chase walls (old cables were just laying behind plinth - including cooker 6mm and induction hob 10mm cabling, I was lucky that the ring and induction cable was even there, if you need to get a new circuit - price that in, that's notifiable and not DIY. we put a proper isolator switches and new sockets and backboxes and ran all new 2.5mm for the ring - basically a rewire of the kitchen ring.
then the cabinets were just attached to the bare brick and patches of plaster painted in 80's paint and various paper styles... this all got knocked off with the chasing and then bonded and plastered.
I got a builder in once the room was plastered and electrics sorted to finish the rest, we got our units from IKEA in shaker style for 1.6k inc worktops, all appliances integrated, new hob, cooker and fridge freezer. circa 1.5k for appliances.
Due to IKEA having no service void I had to reposition the plumbing to below the cabinet height, using pushfit, easy job.
Builder did all fitting of the cabinets, worktops, new floor tiles inc levelling and also tiled the walls, labour came to £120 a day and he took a week and did a cracking job! worked 9am until 6-7pm most days! never saw him take a break!