swirls from the sander. jumping grits too fast. ie, going from a 40 to a 150. Not saying thats what he did, just saying those are swirl marks that weren't properly sanded out.

is this the finished product? stained and top coat?? is the entire floor blotchy like that bottom spot? were they completely stripped? do you have pics of progress?

Definitely skipped too many grits.

The floors are not finished just stained and not top coat. I’m finding a lot of problems and not sure if I want this person to proceed at this point with my entire first floor.

Why does my sanding disc cause swirl marks?

https://www.woodworkingnetwork.com/best-practices-guide/sanding-and-finishing/why-does-my-sanding-disc-cause-swirl-marks

One of the most common problems in woodworking finishing applications is swirl mark, also known as fish hooks.

Determining the causes and solutions, it is useful to evaluate four main factors in the finishing process:

the air compressor

orbit sanders

operator training

and OR the sanding disc.

Have you brought this to the Floor Refinisher yet?

What did they say?

Better bring up now before top coat.

Tell them you want it fixed and want to inspect before top coats go down.

He did this yesterday so I sent him a text today asking to talk about them. He didn’t seem to have a problem with his job yesterday and told me just to blue tape anything I saw. That’s a lot of blue tape! Would you let this person continue at this point even if he offers to fix?

It depends.

If he owns his mistakes and offers to try again, then I would give him a chance to do 1 area & prove his skills.

If it works proceed, but tell him you want to expect daily.

If he can't fix it to your satisfaction, I tell him it's not going like you had hoped & find someone else.

If he doesn't own up to the mistake or problems & has nothing but excuses. Find someone else.

That's what I would do.

Trust your instincts.

Horrible sanding job; it's a do-over. He knows it isn't right. Give him a chance to fix it, please.