That is correct, unless the site is a properly licensed residential site.
In which case, to increase the pitch fee for any reason other than RPI, there has to be a consultation with every resident, and if a MAJORITY of residents declare that they do NOT agree with the increase, then it cannot be imposed.
Of course, if the majority either agree, or (more usually) do not respond at all, then extra costs can be added to all.
(Sorry about the capitals, for some reason it will not let me use bold, underline, or italics for emphasis).
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