You are looking at land rental, putting up the billboard itself and artwork setup, changes and you have to sell it!

Rather than replacing the carpet with hardwood and painting the ceiling panels to make it look more rustic, I could just paint the walls a textured white / grey and add artwork of the Smokey Mountains themed for the winter time: I could then stain the hardwood in the halls white much like this: 

I am costing right now with Postcardmania.comI haven't used them yet, but got the costs so far:$275.00 to print 1,000 pieces (you don't need to mail all 1,000 and can save what you don't send)$0.27 each to mail them.Total: 0.55 to print and mail them combined.They can also do the artwork for $99 and up, if you don't supply it.I don't know if they will do only 100 cards, but it is worth a call

Forget for a second that we live in houses and just think about any other "rare" investment - artwork, for example, or rare books, or rare coins.

Hugh Hefner themed artwork comes from eBay.

I don't know...I kinda like the artwork on some of the walls. 

Or do I sell everything, patch up the walls from hung artwork and wall mounted TV and list as a regular long term rental?

I just think it needs some additional artwork and extra lighting and decor to make your dark green walls really pop and give it that extra wow factor. 

Are you screwing (removable personal property) or nailing (building improvements) in artwork?

Neutral colors allow greater flexibility for tenants, and they can add their own color choices with pillows, throws, art work, furniture, etc.