Along the same lines, adding bedrooms is basically free in terms of additional maintenance. Especially if you are not actively using them. All you will need to do is vacuum/sweep and dust in there once a month, maybe less often than that.
The only marginal financial cost will be energy required to heat and cool the space. Seeing as the original commenter is in the SeaTac area, with a temperate climate, one would think total energy costs tend to be low (I do not live there so I could be wrong).
The only marginal financial cost will be energy required to heat and cool the space. Seeing as the original commenter is in the SeaTac area, with a temperate climate, one would think total energy costs tend to be low (I do not live there so I could be wrong).