Dive/swimspeed question

Aloha I’m a free diver from Hawaii there are some good spots to dive but usually use a boat to get to them since the spots are far out so it’s not worth the swim cuz you be really tired by the time you get there…
I build surfboards here and there so I’m going to custom shape something size of a bodyboard/boogyboard but my part is I have no idea on anything electrical and propelled. I’m not looking to go super fast at least maybe a little faster then the speed of an average swimmer. With a person weight of 180lbs. Im trying to make it as compact as I can with reliable running time.

If somebody can provide me with all the main parts I need propeller motor battery size and I only need it to go on and off don’t need to adjust speed. Just looking for the parts I need and where to get them or even if anybody knows a kit I can buy or something I can buy to modify for this project. Trying to do it as cheap as possible not like use it two or three times and it breaks type of cheap but not so much money where I could just buy a kayak and put a trolling motor on it.

See my first thought was a trolling motor and I battery and just shorten a trolling motor and build it into a board. But then thinking propeller on those are really big usually use a car battery after that I just started confusing myself trying to think.

:call_me_hand:t4: MAHALO :call_me_hand:t4: