Also, look at:	Outboard Outboard motors for a boat are developed as a self-contained unit with engine, subsidiary systems, and propeller, designed to be mounted at the stern (rear) of the craft. They are the most common method of propelling small watercraft.			related sites
Sidenote In bareboat chartering outboard motors are usually 2-4 HP and are carried onboard the yachts in order to power the tenders.  Sometimes they are offered from the charter agencies/boat owners as "optional extras" -under a weekly fee, when by some (especially for charters on yachts larger than 40 ft) they are offered for free as part of the vessel's inventory.