Considering I've driven past buses covered in bumper to bumper ads for McDonalds, the local hospital system, and a pawnshop this morning, I think it's safe to say getting your name and logo on a vehicle isn't an insurmountable task. I would consider starting a helicopter-as-a-service to be the greater challenge.
They almost certainly don't own the helicopters, that would be an extremely large cost for them (up front) including maintenance, staffing, storage and so on. Virtually no businesses actually own their own birds. Their USP is that instead of going to the owners and chartering the chopper yourself, they'll match you up with other commuters and you pay your 5th or 6th of the cost.
