Buena Vista will probably be the most convenient but it also seems to be the most expensive being as it's on property.
I went on the BBB website. None of them is "accredited" by the BBB so I checked ratings.
I couldn't find Best Price Scooters and Strollers on the BB website at all.
Scooterbug had no BBB rating at all, but they do seem to have the best prices for longer trips, not so good if it's a 1 or 2 night trip, but since you've been planning this trip for 2 years I doubt it's a quickie?
Apple Scooters has an "F" rating by the BBB and they specify 6 complaints filed against the business, with a few of them getting no reply at all from the business.
Buena Vista has a BBB rating of A+, meaning they either have few to no complaints, OR they handle what complaints they do get in a timely manner, or both
Were I in your shoes, I'd opt for Buena Vista. Good luck and I hope it's still as enjoyable a trip as possible.
As was this reply, by leaps and bounds.