decorative concrete floors are expensive?

That depends on the company. If the company is dumb and buys all of their prints for the floor Yes it will cost a pretty penny. However if the company just buys the design book and rents the prints it will be cheaper for them and possibly for your neighbor. That also depends on other random factors but that's the gist of it.

That was quite informative. They have started renovating their living room, i dont know exactly which brand they have bought but it was looking decent .

Concrete flooring comes in different types and variety from an affordable range to an expensive one. It depends upon home interior and home owner's decision.