Trying to plan ahead so any know if card payments are common at hostels in Benin or cash is king?
I'd be very cautious about relying on card payments. The reality is that the financial infrastructure for card transactions is not widespread, particularly outside of major cities like Cotonou. The vast majority of hostels are not equipped to take cards. The best plan is to withdraw a good amount of local currency, the West African CFA franc, from a bank like Ecobank upon arrival and use that for your hostel payments and other daily expenses.
You'll be using cash for almost all your payments. While some higher-end hotels might accept cards, most hostels will not. I was in Cotonou and stayed at a guesthouse that only accepted cash. My advice is to assume your cards won’t work and get local currency from an ATM. Make sure to withdraw from an ATM located inside a bank during business hours for safety.
Cash is king, and you'll rely on it heavily. I was just in Benin last year, and I'd say it's 95% cash for everything, especially for smaller, independent hostels. Even if a place says it takes cards on a booking website, the machine might not work or they'll try to charge a hefty fee. I'd recommend taking out a good amount of West African CFA Franc from a bank like Ecobank and using that for everything, including your hotel.
You're going to want to carry a lot of cash. While some of the more modern, digitally savvy hostels in Cotonou might accept credit card payments, like Little Monkey Hostel which is a cashless property, it's not the norm. Most local hostels and smaller guesthouses will operate on a cash-only basis. The country's economy is still very cash-centric, so you'll need to hit up a bank or ATM upon arrival. Be sure to have smaller bills as well for taxis and local markets.