Rental floors in a C or D area

[Chris Utter]

I recently have purchased my first rental property that only needs some cosmetic repairs. I am doing all repairs myself. The debate I have going on in my head with the floors is this...

The floors in this duplex are original and squeak ALOT. They are not in bad condition, few minor stains, few replaced spots, and a good amount of screw holes. There isn't any sub floor.

Floors for one side: Link1, Link2, Link3, Link4, Link5

Same side but photos of everything(tile floors were ripped up for hardwood you see in above photos): https://photos.app.goo.gl/uKDf...

The other side is similar but much dirtier, and a boards will need replaced depending on the direction I go.

Here are few options I have floating around in my head:

1. 1. Refinish the floors and stain with a darker stain
   1. Nails in replaced floor will damage sander
   2. Squeaky floor will still be an issue
      1. Brace the floor boards from the basement may help first floor
2. 2. Rip up floors and place sub floor and new hardwood
   1. $$$$$$$$$
   2. Time
3. 3. Place 1/4 plywood and carpet
   1. Capet needs replaced often in this area
   2. squeaky floors may be fixed with plywood
4. 4. Place Vinyl flooring down(Link)
   1. May be able to place 1/4 plywood and/or brace floor boards from basement to help squeak
   2. Cost will be around $1200 a side

What do you think?