Price is the first search in the trade and the worst answered. A page of prices by vehicle type surfaces better than any amount of description about the centre.
"Expired" is a search of its own with panic behind it. Explaining what it means and how quickly it can be sorted brings the booking from somebody who wants to act rather than compare.
Each vehicle type is a niche: van, motorhome, motorcycle, classic. Little competition, clear intent, and most centres don't give any of them a line.
The early-test rule is the quiet win. Explaining that testing up to a month early keeps the same expiry date brings bookings forward by weeks and almost nobody writes it down.