Most travellers reach the Sahara from Marrakech. Leaving from Agadir instead puts you on the southern road through Tata and Foum Zguid, a route few visitors to Morocco ever drive, and it brings you to Erg Chegaga rather than Erg Chebbi. Chegaga is reached by 4x4 over open desert, so the camp sits well away from any road.
The driving is the thing to understand before you book. Each day is roughly 8 hours and 450 km in the vehicle. That is what it takes to reach Chegaga from the coast and back in two days. In return you watch the sun set over a dune field that is rarely crowded. If the long days put you off, the 4-day trip from Marrakech spreads the distance out.
On the first day you go from Agadir through Tata and Foum Zguid into the dunes, in time for a camel ride at sunset and dinner at camp. The second day opens with sunrise over the erg, then the drive home along the palm groves and kasbahs of the Draa Valley. The camp is far from any town, so the night sky is very dark.
Prices are per person: €990 travelling alone, €500 each for two, €407 for three, €360 for four and €320 for five. That covers the 4x4 throughout, an experienced desert guide, the camp night in a private sleeping tent with dinner and breakfast, and all camel rides. If you prefer your own bathroom to the shared washing block, ask for an en-suite tent when you book.
Not included: lunch on the first day, personal items and tips. The trip is private, for one to ten people, and it is graded easy. There is hardly any walking; what it asks of you is patience with long hours on a road most visitors never see.