In reply to Milesy:
"My last house had off street parking and we had still had constant grief with our neighbours over it because the space was unlined and unallocated."
I've had this, the space was marked on the land registry entry so clearly owned, but the developer didn't mark them out.
If I'd owned it I would have marked it myself. But as it was it caused no end of hassle.
IMO, buy a house with a proper, obvious driveway. Which means staying away from new estates, but that's fine as houses in new estates are often crap little wooden-framed boxes anyway.
Neil