The first question you need to ask yourself is:
What is the end result I am wanting to achieve? and the second, What is my budget?
If you are wanting a climate controlled cellar to provide the ideal conditions to preserve your collection, then that is exactly what you need to concentrate on. Get that right before worrying about expensive wine racks and cabinetry.
All wine must be stored at a consistent temperature. The range can be between 12ºC and 17ºC (ideally 14ºC) and with humidity between 55% and 75%.
Remember it is not so much the temp varying 2 or 3º, over weeks or months, but rather the spike in temperature up and down in hours or days.