I am purchasing a house with 1000+ sf of 2006 5/8 Tarkett engineered floor. It's the 3-board type planks. I can't tell if it's glued to the concrete slab or just tight; can't dig into this until I close on the house next week. The sellers must have had multiple big dogs based on the millions of scratches in the floor. Any suggestions for DIY refinishing techniques before I decide if it all has to be replaced? If glued down, how do you get all those planks up? Thank you.

Demoing a gluedown is really hard, you must cut the floor up with a skil saw and then use a demo hammer. Floaters are easier. Are there floor vents you can pull out or check, maybe around a threshold to see a cushion/underlayment or glue.

Also maybe it can be sanded an refinished.

Thanks for the information. I will check a threshold for glue or underlayment since there are no floor vents on a slab. I hope it's floating. I believe this 3mm engr floor can be sanded but the sanding/sealing cost I got in our area of SW FL is $4.50/sf and takes 15 days to cure. I'm not sure I love that floor enough. This is the price I just paid for dark brown cork plank flooring which I laid myself and it turned out lovely. Since I already have the mitre saw and hand tools, I might as well lay this one myself too... The cork is a wonderful product. Doesn't look like a cheap cork board, is soft and warm, has some spring to it for the knees, is so easy to install, easily to keep clean and maintain, and is a very environmentally sustainable product. I'll probably choose this again.

SW Fla?

I doubt it's a gluedown. I did a lot of Tarkett Longstrip back in the day and can only think of one gluedown. It was murder too.

Your post gives me encouragement that this floor might not glued down after all, and I might be able to easily take it up and replace it with something else. Yes, SW Florida but I really don't want tile throughout, even if it looks like wood, because it's so hard on your legs and back. Still leaning towards cork planks...

If you know the difference just tap on the floor and it should sound hollow but not many consumers cannot tell the difference just because wood always sounds a little soft.

I'm a big cork fan myself and install it floating and glue down. The glue down cork tiles do not give as much as the click planks but after your done and apply a finish the stuff is dern near bullet proof to minor water leaks. Plus glue down can be made into patterns or just about any design you want with different colors.
But glueing cork can be touchy, ya gotta be experienced.