Yes I agree!
We have rented from our friend every time but last and never had a problem with "damage"
However I did full inspect our scooters both when we got them and when we returned them which was why I was able to tell him that the damage was not from me. BUT....I didnt take pictures or have them initial (lesson learned)
But when they showed me the damage on another scooter I said thats not the scooter I had, and if it is that damage was not there when I returned it, but they said no one else had it. Basically your word against mine, I had no proof (but neither did they).....what they did have was my credit card with $1000 hold on it....so in the end they won.
But in the long run they lose, because I will never rent from them again and we rent two scooters for at least 7-10 days every time we visit.
I will just return to our friend, or maybe try out Gas as I have heard good things, also heard good things about Tykes too

How much does Gas generally charge?