Overall fantastic convenient location: walking distance to all the nearby sights and restaurants. Expect a narrow climb to the airbnb, a tight shower, and some minor mold problems. But great amenities such as wifi, kitchenette+stove, and iron (esp useful for a rainy day in Brussels).
Check-in process was a little confusing since several parties showed to Hotel Agora at the same time asking for Antoine's airbnb. To clarify, seems like there are several locations owned by Antoine and either owns, works for, or has a strong relation with Hotel Agora. Once you arrive, speak with a concierge at Hotel Agora and they will show you to your airbnb.