Fish finder for boat and kayak?

Is it easy to get a fish finder, mount it on a boat, then take it off later and switch it to a kayak? Do I need any extra parts... cable, transducer, etc....? Any recommendations on a model that would be suitable for both?

Something as basic as the Lowrance Hook 5 & then buy an extra power cord, transducer & mount.  Could even go with a Hook 4 for $100 less.

Something as basic as the Lowrance Hook 5 & then buy an extra power cord, transducer & mount.  Could even go with a Hook 4 for $100 less.

Outstanding. That's all I needed to know, thanks.

You can buy spare transducers for most FFs.

I have the Raymarine Dragonfly7 and I bought a spare transducer so I can use it on my kayak or boat.

Depending on the unit, RAM makes a great mount that fits select 4/5/7 inch head units making moving it from boat to boat SUPER easy leaving behind a far smaller footprint than the regular stock mount.

You can buy spare transducers for most FFs.

I have the Raymarine Dragonfly7 and I bought a spare transducer so I can use it on my kayak or boat.

 +1  Installing a transducer in each boat is the best way to go.  Thats my set up on my 2 kayaks.