There are various ways these management companies are contracted to operate.
Some can be appointed by the owners themselves, some are mandated to be able to run the property maintenance of the dwellings and the cost of maintaining the common parts.
For example, McCarthy & Stone always build schemes where their own in-house maintenance division have the right to run the management of the site - a bad thing, in my view.
Then, there are various different arrangements by which the management costs are allowed to escalate - sometimes tied to the ONS CPI price index - sometimes not by any specified amount - another bad thing to watch out for.
The OP sees to be saying that the new management company unilaterally decided to spend money on a survey and bill the residents for the recommendations arising (road patching).
It is fair enough that they have to show that the site is safe, but this sounds a trivial outcome, if it was the only one.
In the first instance, I suggest you try to find out what contractual obligations have, and the scope of their work, and also the payment they receive for it, and their mandate to do extra work above the contract for additional payment.
Do you each pay a definable management charge per year? - or is it bound up invisibly in the 'rent' payment for the shared ownership?