$1695 for a custom frame is not a lot of money - even for a steel frame.
However I would ask for the name of the maker of the steel - typically should be columbus or reynolds. Since it is a steel frame you will need to worry a bit about rust. There is a treatment called frame saver which they can apply to prevent rust from the inside. Another option would be to insist on one of the new stainless tube sets from ccolumbus (XCr) or reynolds (953). My steel bike is much older, vintage ~1995 but it was nickle plated and therefore will not rust out. If you are in a real dry climate you may not have a lot to worry about.