Management fee for land that is not shared

ging84

I am looking at a new build property

It is a freehold property, but as part of the sale i have asked to pay in to an agreement where i pay a management company to maintain a 'shared' area. This is an area to the rear or my property, which is used to access my garage and parking space.
The problem is that it only accesses my garage and my parking space, no one else has any parking in the area, there is one other property which has a garden gate in this area but that is it. We were told about there being a maintenance charge when we reserved the property, but we were told that other surrounding properties would be paying in. I was a little suspicious of this which is why i looked into it.
I have now received the budget for the maintenance charge for the whole development.
It shows my plot number as paying 100% for this shared area, and none of the other surrounding plots paying in a penny.

I do not actually object to being solely responsible for the maintenance of this area, what i object to is the involvement of a 3rd party
Looking at the costs break down more 60% of what i will be paying already goes towards management and admin costs, rather than actual maintenance and i can imagine once the contract is signed these will creep up and additional unnecessary services creeping in as there is no cap on this in the transfer agreement.

Does this seem unusual to involve a management company to manage 1 person's responsibilities?
Do i have a chance of having this management company's involvement being negotiated out of the transfer agreement or will the developer likely just say sign it or find another property?