The best model to go for is the L series Diesel. I'll tell you why. The 1.8 petrol engines are dreadful if poorly maintained. The headgasket material on most models is just too fragile, and the rubber joints lose their bonding. The 2.5 V6 models suffer from exactly the same problem, but cost nearly 3 times as much to sort out. Look at £550 to sort the 1.8, and approximately £1300 for the V6 petrol.
The BMW sourced Td4 is also a weak engine, suffering from high pressure fuel pump failure, injector failure at £600 a set, and the turbo is too low on the engine. Failures occur when you go through semi-deep water, and it super-cools the turbo when it is red hot, cracking the casing, or tuining the alignment of the turbine, causing catching or seal failure.
The L series diesel is Montego/Sherpa derived, as also fitted to the Rover 200/400 of similar years. Designed by Perkins, it is a robust and torquey unit, as long as you keep the coolant regularly changed every year, and the timing belt and oil change intervals adhered to, you have a reliable engine.
The drawbacks with the Freelander are these. The IRD (intermediate reduction drive) Transfers drive to the rear axle through 90 degrees, to the rear propshaft, and into the rear differential unit. The Rear diffs are prone to oil leaks and mounting failures(£350 reconditioned exchange), the rear propshaft viscous coupling also fails regularly at £600 a time + fitting, The rear tyres wear incredibly quickly if either of these are faulty, recogniseable by a "castellated" inner tread face, and trademark rumbling noises from the rear of the vehicle. The IRD suffers also if the prop or diff fails, and these are expensive to replace, and hard to find second hand. As hard as it is to say, you would be better off with a Vitara diesel (Peugeot XUD sourced) or a Rav4, or indeed a Honda CR-V.
Engine reconditioner, Land Rover nut, (currently got 3, 1961, 1970, and 1991)