Just give them some random password. They're not going to test it on a device for every visitor. If they come back after a few days saying your password doesn't

Just give them some random password. They're not going to test it on a device for every visitor. If they come back after a few days saying your password doesn't work, just tell them you changed it for security purposes. If they do force you to give a working password at the point of entry, keep a random password generator like last pass and tell them you use a random password generator.