If you want to know the legal (rather than ethical or goodwill) position, I believe it hinges on what the PM told the handyman. (I'm sure, and grateful, that thatbum will correct me if I'm mistaken!)
If the PM told the handyman to do the works, then the work was authorised by you - as you've given the PM authority to act for you in this regard; the PM's agreement is legally indistinguishable from your agreement - and you have to pay the handyman.
Whether you have recourse against the PM for their mistake is a separate matter that would depend on your agency agreement, but I'd be willing to bet that the agency agreement indemnifies the PM for their mistakes in managing your property.
If the PM did not authorise the works, the handyman isn't entitled to be paid.
Whilst acknowledging that this situation is certainly one that warrants negotiation of a reasonable compromise rather than "lawyering up", I do find that knowing where it would likely go if I did push a matter "all the way", certainly informs what compromise I'm willing to consider reasonable.
If the PM told the handyman to do the works, then the work was authorised by you - as you've given the PM authority to act for you in this regard; the PM's agreement is legally indistinguishable from your agreement - and you have to pay the handyman.
Whether you have recourse against the PM for their mistake is a separate matter that would depend on your agency agreement, but I'd be willing to bet that the agency agreement indemnifies the PM for their mistakes in managing your property.
If the PM did not authorise the works, the handyman isn't entitled to be paid.
Whilst acknowledging that this situation is certainly one that warrants negotiation of a reasonable compromise rather than "lawyering up", I do find that knowing where it would likely go if I did push a matter "all the way", certainly informs what compromise I'm willing to consider reasonable.