Ben,
Reservation site
e.g.
http://www.planyo.com/ (multi language)
https://reserva.be/ (only for Japanese)
It's better to use these site rather than Geeklog plugin, maybe.
Reservation plugin is too big development.
I want Maps plugin's category of marker. add display on/off button to maps.
Maps plugin is needed as plugin.
Geeklog Japan
https://www.geeklog.jp