It is possible to force your laptop to use the keyfile even if both the password and keybased approach are available. If you're currently connecting with ssh [email protected] -p 22, edit ~/.ssh/config and add:

Host your.host.tld

    PreferredAuthentications publickey

This configuration file can be used to make you type even less:

Host home

    Hostname your.host.tld

    User user

    PreferredAuthentications publickey

    Port 22

With that configuration, you just need ssh home.

It's possible to restrict password-based logins to a certain IP address. In /etc/ssh/sshd_config, you'd have a line that disabled password-based auth: PasswordAuthentication no. To enable it for logins from a certain IP, you could use:

Match Address 12.34.56.78

    PasswordAuthentication yes

I suggest you to use keybased auth even if on work. It's much safer than password-based auth as it cannot be bruteforced that easily. You can have multiple keys for the same account, that should not be an issue.

For more fancy configuration directives, see the manual page of ssh_config(5). (for the server side, see sshd_config(5))