@Virginia579I'm a bit confused - I'm not sure whether you're asking about a keyless lock on your bedroom or the guest's bedroom. I have a similar situation to you. I now have a keyless lock on the front door, which I highly recommend. Prior to that, I was constantly having to get new keys cut because guests would accidentally take them, not to mention the security issues.
I do not have a keyless lock on the guest's room - as @Emilia42 said, that would not really make sense as I would have programmed it myself. I have thought about putting a simple bolt lock on the inside of the door to help guests feel secure, but given that I am a single woman living in the home, I'm guessing that it wouldn't be much of an issue for most people.
I do, however, have a (keyed) lock on my own bedroom door, which I can lock from both the inside and the outside. This gives me security in case I ever feel uncomfortable (which has only been once in four years), plus if I am going to be away with guests in my home, I can lock it from the outside.