Creating a Building Directory to promote your business

I was walking the other day around the Blacktown Area in Main Street and I observed this building directory (image above) where people walking by can get to see what kind of businesses they can find inside the building.

I believe this is a good idea for promoting a business without making it to fancy or spending a lot of money.

Business Idea: Digital Advertising at Food Courts

Businesses are prepared to pay a lot of money for advertising if you get to prove them that lots of potential customers will see their ads.

I have observed this round thing at shopping centre that are screens loaded with ads that customers at Food Courts get to see.

I assume this technology might not be cheap but returns might be juicy.

Do you think this is a good business idea?