Fire Safety Regulations

After our recent AGM, going over outgoings, it was discovered the company handling our fire safety had charged $2,300 odd for the previous year.  We understood it should be around $1,000, and expressed concern to our Strata Manager, suggesting that we were perhaps being over-serviced.  The Manager offered to get other quotes, which have not yet been forthcoming.  When I approached the company directly to query a $240 charge for attending to a ‘chirping’ smoke detector in the lobby, implying it was a lot of money to replace a battery, I was told there was a call-out charge of $220 and so they thought it was better to replace the whole smoke detector.  Are we being ‘over-serviced’?