So if I have this right you rented a car that was pretty much the bottom of the barrel size wise, and are mad because it was pretty much the bottom of the barrel?
That's not exactly right. Allow me to defend the OP, even though I disagree with the OP's conclusion.
The OP used Hotwire to book "one level up from the lowest car class." The bottom size is
Economy ("Chevy Aveo, Hyundai Accent, or similar**" according to Hotwire). The next size up, which the OP booked, is
Compact ("Nissan Versa, Toyota Yaris, or similar**" according to Hotwire). According to the "**" footnote, "The makes/models shown are examples only. We are unable to guarantee a specific make/model. Actual makes/models are subject to availability and vary by supplier."
The OP would have been very happy with a 4-door Nissan Versa sedan or a 4-door Toyota Yaris sedan. The OP would would also have been satisfied with another car that had enough room for 2 adults, a young child in a carseat, and a modest amount of vacation luggage. The OP likes Compact cars.
Instead, Budget assigned a 2-door Yaris hatchback, which is a smaller type of Yaris. The OP was surprised and disappointed.
Yes, it's a Toyota Yaris, which is one of the Hotwire's examples. And Budget's own description of a Compact includes that it can be a 2-door or 4-door. (Even Budget's Full-size and Premium cars can be a 2-door or 4-door.) Technically, Budget lived up their end of the deal.
However, a 2-door Toyota Yaris hatchback really is similar to the Economy models that Hotwire listed. The Budget counter then offered a Mini Cooper, which, although technically an upgrade, was just as impractical for the OP as the 2-door Yaris hatchback.
So the question is... Was the OP assigned a Compact car or an Economy car by Budget?
The OP had to pay more to get an adequate car, and even it was a hatchback, not a sedan. The OP didn't like the way that Budget dealt with the situation. That's why the title of the thread is "Will never use Budget again!!"
I pointed out that the same thing could have happened with other car rental companies too.
I normally book larger cars as rentals than we drive at home.