Re: 150 or 200 4 stroke
I have a Yamaha f150 on my 21 foot Hurricane, and I'd say it's a perfect match. I can hit 40 mph, and on this boat (Sundeck 217), that is about as fast as you would want to go. Hurricane deck boats are a little bumpy due to the hull design in rough water, so that will limit speed. If your friend is getting a 23 foot boat, I'd definitely recommend the f200.
The f150 is very reliable, and I know of no problems. Maintanance is fairly easy, and I do all my own. Gas mileage is also good. The f200 is 6 cylinders versus 4 on the f150, so you will pay more at the pump.