Well, the floating solution is simply pipe dreaming. Technically it is certainly doable, but financially it is surely ruinous and probably not even approvable. mainly celebrates his wordplays, sometimes content is less central there, one should not be bothered by that. Although it sometimes leads me to completely overlook his posts, which is actually a shame. Often his thoughts are valuable after all and the occasional phrasing quite amusing. In my opinion, a bit more targeted wordcrafting would do the forum good. A new roof is not unprofitable, the alternative is to generate no income at all. If it leaks inside, even the toughest tenant moves out. It seems to be an heirloom anyway, so you have to invest a bit if you want to keep generating returns. In the Voreifel area, adding stories probably won't pay off that quickly, so have the roof done well and cheaply, you can depreciate it anyway.