I picked up a new Wyze camera for $25 on Amazon last week. It connects to WiFi and the app allows me to view it from anywhere on the Internet. It works at home, but I haven't been successful at the marina. It needs 2.4GHz WiFi to work. My marina may be 5 GHz only. I will try it again soon though. The Wyze camera can send alerts for both sound and motion. It would hear my bilge alarm go off and send me a notification.
Jake