You have some options. The keybox is one example. However, you said you wouldn't like the guest to have unlimited access. Every time you give out a physical key, you run the risk of a guest having it copied. There is no way to prevent this. That means if you do want to go with a key, you need a secondary operation to keep guests from coming back. We use an alarm system. We provide the guest a key and then we provide them, once they are actually here, an alarm code personal to them (last 4 digits of the phone number work well). Our alarm system can be monitored and controlled remotely and it keeps track of who armed and disarmed the system. If we are not available when the guest is checking out, we ask them to set the alarm and drop the keys - we have a locked mailbox for this. We then remotely set the house alarm to arm both the motion detectors and to "no entry delay" meaning they don't even get the 60 second buffer to disarm.
We've stayed at other Airbnbs with keypad locks - these also work great but you can't change the lock codes remotely so you have to be physically on site to change the code between guests.
I've not used York, but if you can only send "keys" to the guest via the app and you have guests traveling from oversees, they may not be able to use this service since their cell phones may not work.
Some people use the camera doorbell, when the guest gets to the doorbell, they text you and you remotely let them in via the alarm system or a door lock after viewing that it is actually them at the door. Schlage offers one that you can disarm remotely for the guest via app - but that will require you to be available to do so when they arrive. Same problem with connectivity and some guests.
ADT provides an entire service that is cloud based. You get the alarm system and remote door entry options. Then you can leave a physical key inside the residence for the guest to use.
To put it in perspective with regards to cost.... digital door lock runs about $250 - $300 (one time cost). Alarm system $50/month ($600/year - every year). Home insurance deductible in case your key-maker comes back unannounced $500-$1,000 plus the cost of your stolen stuff not covered.
Personally, I like my key and alarm system combo coupled with my House Rule to use the alarm system and my introductory conversation with a new guest, "We've hosted almost 400 guests over 2 years. We have no idea how many keys have been made. We ask you to help keep all of us safe while you are staying in our home in case a past guest has suddenly become a zombie and thinks he come back to eat our brains because he has a key."
Good luck.