A houseboat is rather less expensive
I am pretty sure that out of two equivalent houses the one which floats would be noticeably more expensive, and more expensive to maintain, too. Houseboats are typically less expensive than houses because they are smaller and less convenient.
As per a recent comment this thread is meant to voice contrarian opinions, that is anything this community tends not to agree with. Thus I ask you to post your contrarian views and upvote anything you do not agree with based on personal beliefs. Spam and trolling still needs to be downvoted.