Just done the same thing myself, (for about the same money, 2K was my budget).
Search on here for the body issues, but I think you are looking at
Boot floor,
Sills,
Wheelarches (rear inner)
Inner wings (front)
I bought a 300 manual, runs fine, (heater works like it should!) minor electrical issues, but all the locks and windows work.
Mine has BIG miles, but has reciepts for a clutch and timing belt kit.
So far, I'm happy with mine, it was bought as a bit of a project, so I knew I was going to do some work on it myself. I can cope with a mig, and most other things are straight forward.
Thanks for the reply, Ive heard the rear floor is quite an issue on the discovery for some reason also sills, I have been running classic Range Rovers for years, but had a look inside a discovery and was impressed with the amount of space you have in their plus the seats can either be removed or folded for extra room. I know the running gear is the same but its the issue with the rear floor, I do have welding gear but worry the floor issue may be a reoccurring problem, owning a classic rangy I know the rot problems with them and have easily addressed it. I was also told but dont know how true it is the discovery is known for gear box problems.
Look around, and find one that suits you. The values are a bit high just now, (wonder why ???)
There are plenty about, some worth avoiding tho