If I were NASA I would think of sending a Lunar non human mission to install robotic lighting instruments to the visible (near) side of the moon, for terrestrial telescopes to detect messages information and "even advertisements" especially when these instruments are shadowed by earth during the crescent phase.
Possible project of this type may cost around 300 Million USD (almost cost of a bridge or a highway) which would have immense returns of different nature including:
1- Increased awareness of public about Space missions
2- Proof of Lunar landing
3- Advertisements via radio controlled light emissions (text or even simple video)
4- Research data on Lunar installation of renewable energy systems for a future moon station
Any of the above would be worth the cost, but more than all is
5- Having the honor of first permanently operating lunar system...
The project would involve activating solar panels to collect energy during the solar exposure phase and turning on the lighting instruments during the shadowed phase. All it would require is NASA radio control station to operate it (them) and telescope(s) for the public to observe the operation.