After our first 6 months free keyholder service we paid the Polaris fee for another 6 months last August, only to find that Polaris withdrew the key holding facility around October due to budget cuts. We only discivered this when we tried to give someone access to our appartment last year.
Polaris put us on to a company who are based on La Torre, who I have found to be very good and much cheaper than Polaris. I don't have their contact details with me right now but is anyone want the details just send me a provate message. Our understanding is that one does not need to have a key holder, but we have found this well worth the investment and the new company even check out the property every month to ensure that there are no problems. When people such as suppliers have access, they take them to the appartment and make sure that nothing goes missing.