Hello welcome, good news about he cambelt change service & m.o.t included in the sale, you shouldn't have any problems and it will cope with nearly eveything you used to throw at the defender, may get a bit stuck in the deeper stuff but thats about it. If driven sensibly near 30mpg isn't too hard to achieve.
The exhausts tend to rot from the outside in so look alot worse than they are what kind of milage is on it ?
We're all friendly on here so any questions or random atuff you may need answered don't hesitate to ask.
I'm sure after about 5milws of driving it away you'll be smiling