There is a guy I know in Brampton who put a 10ee in the basement (no longer there,was sold). He went through the garage floor and tunnelled. Cover plates of steel made the garage floor still usable and a chainfall and gantry system did the lifting. I admire his no-compromise attitude but you'd have to be young and a bit crazy to be up for it, a LOT of work and potentially impactful on resale value. Nice old boy, real craftsman, was a toolmaker at Spar Aerospace.