You need to agree in advance to these and any other bills if they were not included in the annual budget, so says the Act (somewhere). I’ve seen it and explored this when the committee just thought they’d get some exclusive use cleaning done to balconies. If there’ is no prior agreement it just doesn’t fly nor are you compelled to pay for it. Imagine if you could have done it yourself, or it gets priced at a totally stupid price, or just wasn’t necessary? – so, they’d just expect you to pay it? No way. Your annual levies are different, and you knew and agreed to these at the AGM each year. Not paying the others is a different issue. Tell them, they’re dreaming. Find the case history from a number of adjudicator decisions to prove your point.