Short answer: Ask for the locksmith's business name and GPPKM member ID, then check it against the GPPKM member registry; confirm the person matches the listing; expect them to request proof of ownership before opening any lock; and agree the scope and price before work starts. Membership is one trust signal — not a government licence or a guarantee of outcome.
GPPublished by the GPPKM committee · a registered trade association. General guidance, not legal advice.