Glencoe was built out largely between 1915 and 1940, and it was built well. Tudor Revival, Colonial Revival and a handful of notable mid-century houses sit on wooded lots that are large even by North Shore standards, many of them on or near a ravine. There has been steady teardown-and-rebuild activity since 2000, so a newer house on an old street is common.
The houses are generous and the original bathrooms are not. A 1920s house here was designed with one substantial bathroom and two small ones, all of them built around fixtures that no longer exist. The work almost always starts with the same question: where does the extra width come from.
In a house of this size the answer is usually available, and the cost is usually in the plumbing rather than the framing. There is generally a closet, a back landing or an oversized hall to borrow from. What decides the budget is whether the supply and the stack serving that corner of the house have already been replaced, and that is settled with the walls open, not on paper.