I end up getting a 18-ft fiberglass center console (SeaRay Laguna)
instead of an aluminum. The reason is that I really have no idea how
to fix an aluminum boat, and fiberglass boat looks very nice.

That boat comes with a 115-hp Mercury outboard motor. The motor got
the boat on plane in just 5 seconds or so from displacement speed (plus
or minus, who was counting anyway). We had 4 adults on the boat, I was
expecting that the boat would take longer to get on place. I was
pleasantly surprised that the boat/motor combo worked quite well
together even with 4 adults on board.

The boat got on plane and at cruising speed with 2/3 throttle at around
4,600 rpm. Putting the motor at full throttle didn't seem to increase
speed much and the motor only increased to around 5,000 rpm. This
means running the motor at full throttle didn't buy me anything.

I posted this just in case someone wants to know what ended up
happening.

Jay Chan