Open face helmet communications query

The wife and I both have Bell Custom 500 open face helmets.
We are off to Spain in the summer and I am considering moving away from maps and acquiring some simple form of rider to passenger communication and a link to a sat nav device.
I am totally ignorant in relation to these matters although we have an old Garmin sat nav that is used from time to time in the car so I am familiar with that and would possibly look to get a Garmin device for the bike?
I do not have a smart phone and would want to keep things as simple as possible.
Any advice would be appreciated.

Curly

 

Thanks Tim, I'll look into that.

Curly

 

Will do, thanks Littleade.