I've been inspired by my friend's hotel in one of his worlds and I decided to make one myself. I call the Hotel, Mountainside Hotel. It's built into the side of a mountain (Obviously) and it is built nearby an NPC Village.
I plan to have shops throughout the Hotel for the guests to enjoy. I've set up the currency system which is posted on a sign outside the Hotel. It's set up so that 1 Gold Ingot=2 Iron Ingots, 1 Diamond=2 Gold Ingots and 1 Iron Ingot, and 1 Emerald=4 Diamonds.
Please leave a Diamond if you like my Hotel.
On a side note: Each room has an Ender Chest for each guest's items so that no one else can take their stuff from it if they break into their room. Smart, huh?

I've decided to scrap this idea. Feel free to download the world to continue the Hotel yourself if you want.

Additional Notes

It's still a work in progress but it is progressing.
I actually have a guest in a Luxury room. His username is tigeriz and he's a good friend of mine in real life.