Satin. We had some Scandinavian oil used on our Cypress Pine floors. Not sure of brand but its quite expensive when compared to the other brands. The key is a good operator of the sanding equipment too......

All the joinery and floor finishes are brand new - the old ones were not in the best condition, and the layout was not working well, so it had to go!

It is a great improvement . However I always laugh at all the before and after photo's on a lot of renovations on Houzz -- take the before photos on a dark day with the lights off ; do a reno ; take the after photos on a sunny day with every light ( and flash on the camera ) , and say how bright and breezy it looks ! It's like every weight loss 'con' -- the before photo in frumpy clothes with no smile and minimal lighting -- the after in a bright outfit , huge smile , feet 2 foot off the ground grabbing up for a beach ball , with lots of lighting !

Wow, not only did you do a fantastic renovation on the whole apartment but you also made your clients financial needs a priority. Well done on a beautiful job.