The house has a laundry shute, right?
Use a bucket only partly filled with aquarium water, carry them downstairs, slowly add water from the new aquarium. When the bucket is full, dip water out and put it back into the new aquarium. When the bucket is half empty, start filling the bucket with aquarium water again. The purpose of this is to get the Ps acclimated to the temperature and water perameters of the new tank. You don't want to stress them by just dumping them in. After the second bucket change they will be ready for the new tank.
