I always rent a drum sander, thick grit sanding rolls ( 24-36 grit) for the drum) sand the f out of existing hardwoods.

Go home, figure the sq. footage of each room...drum roll please.....and go to the Home Depot website, and use their project planner tool.

Try to get one where it is more of a drum type sander than the big disc sanders.

A good rookie agent will spend hours per day on the phone trying to drum up leads.

Most love having a garage and NOT having neighbors "bang on the drum all day." they also love not having to go up & down stairs. and if you have a fence, you're golden with kids & pets.

Drum is particularly  vulnerable going forward  i would think 

I winterize a few houses for customers who winter in Florida , first I shut the water down at the street , then we drain everything , kill the electric to the water heater , tape over the breaker , blow the house out with a 125 cfm diesel compressor , then we have a 55 gallon drum of RV antifreexe and we use a air diaphram pump and fill the pipes with the pink stuff.

It is time to march to the beat of a different drum.

A drum sander from Home Depot is the way to go, IMO.

If you do decide to go with finishing the hardwood, make sure you rent one of the drum style sanders instead of the disc sanders (big buffer looking style).