Apartment Keys issue

Hey Guys! I’ve been hosting on Airbnb for a year now and I’ve had many challenges which I’ve mitigated except for one big one that’s bugging and I know there are others that has the same issue. Here it goes!

Most concierges at the apartment are cooperative enough to let the guest check in but they need to know who is the person that you’re authorIzing. In some condos there is a website where you can put instructions to concierge but in mine there is nothing as such and I’m tired of getting phone calls from them and then complaints from guests it I didn’t answer the call from concierge.

Now, Ive been looking for a solution where in my head I feel the solution is out there. I’m thinking some sort of keychain that is digital that can be attached to the keys. This can be updated with the guests name through a mobile device by me from wherever I am. Just like the dongle that banks give you to generate a random password. Is this something that’s possible? What are your experiences? Please share.