How long is a piece of string? What kind of rack do you want? Why a rack and not a cage? What kind of plates do you want - cast iron/ bumper/ olympic? What kind of bar do you want - generic cheap ‘n’ cheerful or Rogue? Etc. etc.
Once supplies are back in, you could easily pay less than £1,000 at full retail for what you want from Fitness Superstore simply buy buying the cheapest of everything you want. Or you could bust your £2,000 budget buy buying the best.
If I were you, I would start by having a chat with @aaronru about his kit and, as @ChongLordUno says, keep an eye on Gumtree & Facebook.
The advantage of buying secondhand kit is that any depreciation is likely to be nominal when the time comes for you to sell it and upgrade.
Birthdays & Christmas are ideal opportunities for you to get your kit added to gradually over a period of time at no cost to yourself!
This. Completely agree with the points made here. Im going to assume that OP may not have experience in what to look for when buying gym equipment. Advise referring to this site for insight on how to choose.