Tiles for basement from the hardware store

Calibrated just means for installation that the joints can be chosen smaller. With non-calibrated ones, you have to compensate over the joint. You can easily feel it when you run your hand over the edge of the tile while looking at tiles. I would pay attention to at least calibrated, slip-resistant (R10 or barefoot) and abrasion-resistant.

If you still have a bit of time, keep an eye on special offers or clearance sales. A year ago, I got lucky and got calibrated R10 tiles for 7€. Unfortunately, my tile installer was too stupid to properly lay even good tiles….. I would rather tile one room myself with the tiles now and unfortunately had to buy them at the regular price. DIY store tiles are good enough….
I would recommend a leveling system.

We took 20€ tiles from Jonastone and ordered grout etc. there at the same time. They were not rectified but were very easy to lay in the 30x60 format with a leveling system. We just still need to practice with the joints.

One can definitely look for special items in specialty stores. I have here a Batzner hardware store with tile special items. The whole hall is full of the most beautiful and expensive tiles at clearance prices. I have also already bought the best Italian calibrated tiles there.
Porcelanosa floor tiles from Spain for 8 euros. Experts know what they normally cost.
Sometimes they have floor tiles in unusual colors like blue or even orange for 2 euros in top quality. Well, I haven’t been there for 2 years now. But I once bought blue tiles for 1 euro. I still have them. They might go into the chicken coop someday.
Many tile layers also come from outside and buy cheaply there. The customer doesn’t notice anything. They still pay 50 euros.

The tiler sold us the tiles from stock at €6 per sqm. However, this is only plus the installation service.

from your parallel thread. I wouldn't go to the hardware store for that.

I laid cheap tiles from an inexpensive tile market in the utility room. You can tell when laying them that the tiles are not all perfectly the same size, which causes the grout lines to be slightly different. If you can live with that, they are no worse than expensive tiles. You can also get the same class and quality from the hardware store in terms of abrasion resistance. We had cheap hardware store tiles in the old bathroom, and after many years they still looked just like they did in the beginning. And our children often went into the bathroom with shoes on back then, so they had to endure quite a bit. I also tiled under the heat pump. This creates a uniform surface, which is easier to clean, and above all, with tile skirting and a silicone edge, you have properly sealed the connection from the floor to the wall.

How much waste are you planning for approximately? I will also buy my tiles for a total of 4 rooms this weekend and of course want to plan the quantities accurately.