Bill Kearney wrote:

I'd want to monitor two sets of 12vdc levels, three bilge pumps, two air
temp values (cabin and engine compartment) and perhaps an IR motion sensor
or two.

If you want to monitor this remotely via telephone or internet I would
recommend something like a Elk M1 family device. On the other hand if
you are just going to record the data for later examination the laptop
is the way to go. I would look at serial or 1-wire instead of USB...