Looking to buy

Hi, Just signed up and looking for some advice, am looking to get a cheep (ish) Discovery as a second car, after last years bad winter.

I have in the past owned a Freelander and 2 Jeep Cherokee's (if ok to mention Jeep on here) one petrol and one diesel.

I am probably looking at pre 2001 as I understand Road tax will be cheaper. I am really looking for any advice over models or problems to look for, checks to make. I dont mind going for petrol models as mileage will be lower and likely to get more car for my money if picking petrol i suspect.