Flooring recommendation?

I am looking for a flooring company or individual worker to do what I believe will be a simple floor refinishing project.

I just closed on a one-bedroom apt in Brooklyn Heights. The wood floors are in good shape structurally but could use a face lift. My (sadly limited) understanding of the task at hand is that it might simply require a sanding and a new coat of poly, or perhaps just the latter. If anyone has any general advice in addition to specific recommendations for hires, I’d appreciate it very much (as I’m sure you can tell, I’m new to this!).

Another point: my coop board requires that all workers be insured to operate in the building, so my search will be constrained by that.

Thanks!