Mobility stores are fantastic if you want to go and have a proper look and get a feel of the right scooter for you, but online stores offer much lower prices. If you need to have a go on the scooter before you buy, you can go into a mobility shop and see what's right for you, then proceed to buy online. One cheap online store is Great British Mobility, they also stock a huge variety of scooters from popular to the less common ones. There's different types of scooters to suit your needs and they even offer mobility scooter finance so you don't need to pay in one big chunk:
https://greatbritishmobility.co.uk/mobility-scooters.html . So if you're looking for cheap scooters, have a search around, there are plenty of stores out there.