The second floor is supported by columns in tension, not compression, so concrete is unsuitable – use steel. The tension in the steel is equal to the compression that would occur if the design were conventional, so no additional steel is required over a conventional design, and steel costs are the same.

The third floor now supports the second floor, so measures have to be taken to ensure that the steel supports do not work loose, and that the weight of the second floor is evenly distributed over the third floor. This is the upside down equivalent of the conventional distribution of load.

The outside walls between first and second floor now carry the same load as that between the second and third floors, as it is the same load (of two floors). It is now no longer possible to design the outside walls to be thinner between the second and third floors. However this is not a disadvantage, as the same thickness is conventionally used for convenience, anyway. So there is no cost saving.

If the building is in an earth-quake zone, you should run calculations and simulations to ensure that swinging of the second floor does not amplify the effect of the earthquake, as resonance may occur, depending on your dimensions.

I think a good example you could study or visit is the Hinman Research Building, at Georgia Tech's School of Architecture (USA). Originally designed by P.M Heffernan in 1939, it has undergone in 2011 a $9.5 million restoration, rehabilitation and adaptive reuse by Office dA in collaboration with Lord, Aeck & Sargent. This project adapted the freestanding research facility to include other programs (e.g. graduate level architecture studios, computer and interdisciplinary research labs), and the original concrete and steel construction was retrofitted to a LEED Gold Standard of Sustainability, and has also won some other awards. Without doubt, one of the main features of this project is the hanging mezzanine, that was created by re-purposing a large bridge crane to support a tapered floor structure. You can find more information on the links below:

http://www.bdcnetwork.com/bdcs-28th-annual-reconstruction-awards

http://www.archdaily.com/123220/hinman-research-building-office-da-and-lord-aech-sargent/

The second floor is supported by columns in tension, not compression, so concrete is unsuitable – use steel. The tension in the steel is equal to the compression that would occur if the design were conventional, so no additional steel is required over a conventional design, and steel costs are the same.

The third floor now supports the second floor, so measures have to be taken to ensure that the steel supports do not work loose, and that the weight of the second floor is evenly distributed over the third floor. This is the upside down equivalent of the conventional distribution of load.

The outside walls between first and second floor now carry the same load as that between the second and third floors, as it is the same load (of two floors). It is now no longer possible to design the outside walls to be thinner between the second and third floors. However this is not a disadvantage, as the same thickness is conventionally used for convenience, anyway. So there is no cost saving.

If the building is in an earth-quake zone, you should run calculations and simulations to ensure that swinging of the second floor does not amplify the effect of the earthquake, as resonance may occur, depending on your dimensions.

Thank you guys for helpful answers! I have noticed that in these kind of structures, vibration governs. Do you have any idea or strategy to face this problem?

Damping can be improved by not having supports (from above or below) at exact modular distances apart. Rather introduce some randomness, without exceeding a safe span or making a parking spot too small.

Also, place the main air conditioning plant on its own insulated base, to avoid structure-carried noise or use decentralised split units with the noisy unit mounted outside.

However, re-inforced concrete floors are thick from load-carrying calculations, and vibration is usually not a problem except if one shop or office is renovating and using pneumatic drills.

Don't have grates that people might dance on; don't use inferior construction materials; make sure that everything is supported DURING construction. Read recent newspapers.

Have a look at the Berlin Stock Exchange, or Ludwig Erhard Haus IHK, by Nicholas Grimshaw and Partners (aka Grimshaw). We used a series of multi-storey steel arches from which to hang each concrete floor plate (with  integrated coffered downstand beams) from first floor upwards (like mezannines) to allow for an entirely column-free trading floor at the ground level. It's colloquially called 'the armadillo' and was groundbreaking design at the time.