Below grade space doesn't have a similar appraisal value to above grade space. And there are health and safety codes that apply to bedrooms underground that would not apply to other forms of living spaces. Such as emergency escape and egress and arc fault outlets. Creating a master underground may be more expensive than you anticipate, and give you far less return than you would think. But if you solve those issues, and you are OK leaving the children all alone on the ground floor, then you may get enough use out of it to make the economic expense of the project justify itself.
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Livingroom perfect
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