Your welcome,Tracy. Happy to help and appreciate the kudos. Kudos are great with grits, but isn't everything.
I have used Parks water based poly on furniture and saw where they suggest on the label that it can be used for floors, if mixed with a hardener. So I E-Mailed Parks for more info on the hardener and how to use it on stair treads. They strongly suggested that I use Parks Pro Finisher Oil Modified Polyurethane, which I did. They know more about it than I do and their website is very good and helpful. The stairs have only been in about a month and look great. You cannot tell they have been walked on. I put on 3 coats with 24 hours of drying in between. Since you have not moved in yet, you may think about going this way. The big advantage of waterbased is it's quick drying but it does look a little milky.
Because of space and finishing them before installation, I did them in 3 groups of 5 treads so I got real familiar with the product. It does not like being applied in a real thick coat but seemed easy to apply. I have not tried applying it with a lambs wool pad so can not comment on that but you might check with your paint store or their web site. I thought the price was very reasonable.
Good luck with your floor. Wish it was 50 degrees here. Henry in MI