Good luck if you go for it.
Just be aware of how much profit you might actually make.
Unless you set up a limited company you are already paying 40% tax on any profit.
Add 20% Vat on your margin, difference between buying and selling price.
So if you want to walk away with £500 profit in your pocket by the time you account for all the prep, advertising, etc then you will need a couple of grand mark up.