Lightweight and compact, maybe this is the way to go.

If you've read about hull types and engine types, then you probably
have some idea about the kind of boat and engine you'd like to have. We
will now explore the various methods of transferring the power
generated by the engine to the water.
First, you need four basic things to make your powerboat move:

A power source (your engine).
A propeller or pump to provide push.
A connecting device of some kind, to connect the engine to the
propeller/pump.
Devices to control the amount and direction of the thrust.
Outboard motors range all the way from lightweight 2 horsepower (HP)
portable models, to 350 HP monsters bolted directly to the transom
(stern of the boat) or to a bracket that is then bolted to the stern.
The outboard is basically a self-contained unit, consisting of a power
head (the engine), the intermediate housing (the drive shaft) and the
lower unit (gear, housing and propeller). The throttle, gearshift and
steering are attached to the power head. To change the direction of a
boat using an outboard motor, the entire unit - power head,
intermediate housing and lower unit - swivels, thus changing the
direction of the propeller thrust.

Some advantages of the outboard motor are that they're very lightweight
for the HP that they produce, and because they are located "outboard",
they take up little or none of the boat's interior volume.

Conversely, a disadvantage is that there is generally a cut-out in the
transom for the outboard, leaving the vessel more vulnerable to water
breaking over the stern and coming into the boat. Also, by the nature
of where it's located, the majority of the engine's weight rides
outside of the boat itself. This tends to adversely affect the trim of
the boat, causing it to ride down at the stern.

Best regards
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