21:16 here: also, be sure to have a sealer finish layer between stain and waterborne gloss finish. Again, use 1 manufacturer for all, as they test and warranty based on the evaluation of their products.

We did most of our main floor with oil based recently and it ended up being $3.20/sf. Got 3 quotes and all were $3-4/sf.

I favor oil based poly, as my very expensive water-based poly floors' finish has never stood up to the job. This is in spite of using the company's highly durable waterborne finish after refreshing the floors via a "screen abrading and coating" also known as "buff and coat". Honestly, prior homes oil based polyurethane floors were much more one and done.

The above said, there are still old timers who will do oil, yet most now do waterborne poly. It's more efficient time wise for them, it drys faster, minimal odor and they still can charge.

There are many waterborne polyurethane manufacturers. Look into them, don't buy just the most popular. Ask around. At this point, while sticking with the waterborne manufacturer, we are proficient at doing a room or two at at time ourselves.

As to cost per square feet: I'm not up on that. Yes, I do believe your getting all over the place quotes.

1. Is water-based poly a bad idea? We would really prefer it to oil based because of less drying time and VOCs, but are having a hard time finding someone who is willing to use it and those who don't use it are trying to tell me it's a bad idea. My Internet research is mixed. Some sources say it's better but harder to apply, which would explain why some of the contractors are trying to talk us out of it.

2. What is the going rate per square foot for just the refinishing (not including mouldings, etc.)? The quotes we are getting are all over the place.