What does the contract you signed when you paid say? Almost everyone charges a restocking fee, 25% is not at all unreasonable. Presumably if you liked the flooring you could keep it and get it installed by someone else?

If YOU bought it, how can the contractor charge you a percentage on the material YOU bought? If you bought the flooring, you own it. Find another contractor to install it.

I could keep it but i dont trust this guy. there was no receipt or contract signed. Thats why i want to return it.

Then you would have to pay the return charge, which is quite typical in the industry.