One forum member wants to come back to houseboating and asked a lot of great first-timer questions, including the benefits of gas versus diesel:

Tillerman7: I seem to think that a diesel would be more efficient, but they seem even harder to find.

desimulacra: The only reason I would go with a diesel is if I was planning on doing a lot of traveling. Then a houseboat, like most on this site, is not really ideal. 
As a side note we were sitting out at Rock Port Bluffs the other day and a houseboat went by with gas engines that was very quiet, then one mile behind it came an aluminum houseboat with diesels that was extremely noisy. I mean, the engines were loud. More so in front than the rear. I was wondering if the hull was projecting the sound. Anyone? 
Good luck and keep us posted. 

GoVols: There's always a benefit for diesel when fuel consumption comes into play, but you'll need to put a LOT of hours on them in order to recoup your money from initial investment, as diesels are significantly more expensive than gasers. An interesting spin I saw recently was gas propulsion engines, but a diesel generator.

easttnboater: Gas propulsion and diesel generator—maybe not as great as you think. Typically diesel generators are paired with diesel propulsion. Because of this, in general, diesel generators are not spark-protected. So, I would want to make sure that the diesel generator was fully spark protected/enclosed.

OLD HOUSEBOATER: With fuel costs being what they are, lake boats with small engines are the norm. Good used boats are still the best all-around deal. If you plan on extensive traveling, diesel is the way to go. All that being said, diesel houseboats (other than Pluckebaum) are few and far between.

This post went in a lot of interesting directions as more questions were asked and answered, so don’t forget to check it out at www.houseboatmagazine.com/forum!