Just been doing a bit of surfing and came across summat new to me!
Jumbalance.
Had a good gander around their site,…mmm, very interesting. They take groups of wheelchair users on foreign holidays, going by ferry on a fandabydozey adapted coach,…double deckers too!
Looks like groups hire the buses and pay according to what they need.
Doesn’t look like individuals can go, but need to be part of a group.
They used to use it for taking disabled pilgrims on trips to Lourdes.
In my town , it was also a case of looking for volunteer “companions” who - of course - had to pay their own way.
The reality is that it is adapted from a continental bus, and I believe that it is owned by a charity who want to see it used as much as possible. I think that they have expanded into other types of vehicle, with the disabled in mind. See: