After about 14 years out of the UK I'm returning for 4-5 months and I need to get a car for that time.

Has to be a estate and since I'm going to be doing 2k per month of motorway miles it needs fuel efficient and reliable

I have looked at the long term car hire and it's about 450-800 UKP per month plus the excess

Anyone offer any other options and what type of car should I be looking at, If I decide to buy a cheap S/H car

(bear in mind that it needs to be reliable ;-))