We actually just had something VERY similar happen.
My dad requested and paid for a
scooter for Memorial Day-Thursday. They called the day before and said they were all out and only had the pricier ones left but he would have to pay for an upgrade. He wasn't having it then they upgraded for free.
Well let me tell you what a piece of s*** this scooter was. The battery totally died after only being used on AND OFF for 4 hours. My dad is overweight but nowhere NEAR the weight limit. So we plugged it in the Land building at Epcot while we did Soarin', Living with the Land, ate lunch, and spent some time outside. About 3 hours. Now the scooter would stop and start abruptly and still not working properly. We had to PUSH it out of Epcot by hand. We did call Yellow scooter company and the operator on the phone was SUPER inconsiderste. And said there was nothing she can do and basically oh well maybe tomorrow afternoon someone can bring a replacement. Heck no. Dealt with them and their idiotic company.
Plugged it in the room for a few hours and took it back out that night. It worked until we got off the bus at MK, and then it didn't work at all. We pushed it all the way up Main Street and left it plugged in while we did rides. No less than 4 hours. Still didn't work after being plugged in.
They only refunded my dad half of the money even though we only had this scooter working for 4 hours. Ridiculous. Their manager wouldn't call me back and only had his little minion phone operator make the phone calls because she could do nothing for us.
We called a Disney approved company the next morning at 8am. Best Price Scooters and Mobility or something like that- they had a scooter at the luggage pick up at our resort in less than an hour and said if anything like this happened at the park, they'd meet us within an hour with a replacement no questions asked. We never did have any issues with the new scooter. Lasted a full 14 hour day for us and the battery bar didn't even go down at all LOL.
Yeah I'll agree with this and also say NEVER EVER EVER rent from yellow scooters. If you have issues outside normal business hours you can forget getting any help from them.