The cost of a bathroom depends on three things: the condition of the systems, the size and the materials. The systems are the item you see least and that matters most: redoing drains and pipes costs money, but it saves you from tearing everything open again in a few years.
The main items
Demolition and disposal, plumbing and electrical systems, screeds and waterproofing, wall coverings, fixtures and faucets, installation. In our quote each one has its own line and price.
Where it pays to spend
On waterproofing and faucets: they are the parts that work the hardest and, if they fail, cause the most damage.
