你房子要是有basement 或 crawl space 就很容易。slab foundation will be a litt

Slab foundation will be a little bit difficult. But you may try the macerating shower system which you can drain to the exsiting plumbing with a macerating pump. or if you only have shower and filter all the debris before drain pump, you may try the normal pump which is much cheaper. You may even can filter and drain your after shower water to your flower bed to save some on your water bill.