New construction home plumbing issue. Architects placed toilet in front of bathroom door. What the heck- that is where the sink should be! We did not notice until slab was poured and we saw the drain rough in. We want to move the drain at least 5 feet. This is a pier and beam foundation due to lake location and bad soil. Builder said he can cut into the slab, but I am concerned this will cause possible foundation or plumbing issues down the road. We could move the doorway but that means giving up valuable cabinet space. What would you do?