I would recommend insurance for your dog, as soon as you get him/her IF you can. You may face pre-existing conditions which preclude that however which is why I cancelled mine over here, also too expensive! We opted to open a pets only savings account and add to it monthly for emergencies or big ticket vet visits. Regular routine vet visits we just pay for. Bulldogs can be expensive (not always) but I think they are worth every penny and I am sure everyone on here agrees!! A vet that knows bulldogs really well is very important. Try and feed your dog the best grain free food you can get and I will rely on others from the UK to recommend foods for you.
Someone with much more knowledge than I will be along about the breeding aspect of it. We got our boy through a re-homing situation although he does have papers.
We have had many breeds over the years and have loved them all but there is something about a bulldog that is totally unique. They are such great dogs and I hope to always have one. We got our Chumly, who had a little something else mixed in, from the RSPCA and finding him was one of the best days of my life and the start of our bulldog adventures! Lots of luck in yours!