The château is between the towns of Cotignac (the largest town), Monfort-sur-argens and Carcès. Accommodation in and around these towns is mostly made up of guesthouses and B&Bs. There are also plenty of Airbnbs.
Brignoles is a larger town a 20-25 minute drive from the château that has several larger hotels.
The south of France can be quite busy in September, and as many of the accommodation options are smaller guesthouses we recommend booking early.
Below are a few suggestions to get you started.
Clos de l'Ours
<10 minute drive from the château
6 bedrooms ranging from €180-240/night
Domaine de Nestuby
Small guesthouse on a vineyard with a pool.
<10 minutes drive from venue
6 rooms, €100-200/night
Le Mas de Cotignac
Guesthouse <10 minutes drive from the venue
2 bedrooms and 2 suites from €120/night
Hostellerie de l'Abbaye de la celle
Just outside Brignoles and a 25 minute drive from venue.
Has a Michelin star restaurant.
10 rooms and 5 suites, from €250/night
Hotel Lou Valen
12 bedroom hotel with a pool just outside Brignoles
From €120/night
17 minutes from venue
La Maison de Campagne
<10 minute drive from the venue just outside the town of Carcès
4 rooms from €100/night