Well Sumpcracker has already covered my top choice!
Other options sub £1000, that I would suggest from personal experience...
BMW E34 5 SeriesI just love these boxy barges, especially in touring guise. I've owned various models over the years, the big petrol ones are as thirsty as you would imagine, but the 520 will see 30mpg withouht any trouble and has that great BM 6 cylinder noise.
My model of choice would be a 525TDS manual Touring. My last one averaged mid thirties overall mpg, towed really well, had bags of room and was cheap to service. Rust free ones are still around for sensible money.
Good pointsBig solid barges, seem to wear the years well, particularly inside.
Well specced, generally, nice and quiet inside, great mile munchers.
Parts are cheap and they're not bad to work on.
Acceptable mpg figures if you stay off the big stuff!
The usual combo of a little lowness and dished rims makes them look awesome!
Not so goodRusty ones are plentiful
Electrical gremlins - particularly windows, locking and rear wipers.
Some are on metric wheels, cheaper to re-rim than re-tyre!
Prices on the up, as the scabby ones get drifted and dealers start selling the good ones as 'appreciating classics'.
Second Option
Citroen ZX VolcaneThese are cracking little things!
I've owned a petrol and a TD version of these. Both are nippy little things, great fun to drive and super comfy. The petrol will do 30s mpg and the diesel will run on an oily rag! I think these are better suited to shorter journeys, as they do feel a bit short legged on the motorway.
The goodThe comfiest seats ever!
Great fun to drive
Cheap to buy, run and insure.
Easy and cheap to maintain.
Good economy - diesels are amazingly good.
No-one will understand why you bought a 20yr old French car out of choice!
Not so specialTDs can suffer from hg failure, although most have been fixed by now!
Worn out seats ruin the car.
Trim falls apart and electrics can be 'interesting'
Rot
The thin panels pick up dents quite easily.
Joe