I noticed that the woman that cleans my house brings a large squeegee (like you would use on a window, but this one is mounted on a broomhandle). I assume she uses this on the hardwoods. I don't buy her any floor cleaning products, but she does ask for vinegar every so often, so I guess that is what she is using.
My home is over 4000 sq feet (including finished basement) and I pay her $120/cleaning every other week. My goal is to be able to have her weekly, but that's too expensive for now.
When you hire a house keeper, don't use a service. Get a recommendation from someone that has used the housekeeper for a long time. Also, my housekeeper usually brings a few people with her, so they get done in a couple of hours. My neighbor has one person and she is there for 6 hours. That would drive me crazy. I like them to get in and out. I also prefer not to be there while they are cleaning and to just walk in to a beautifully clean house. It's like a present every 2 weeks.