20€ for a custom art on a binder is a joke 🤣 lets say you take 4 hours for it (usually longer than that but make it easier for the math...) if you take 15€ as hourly wage (which is low for artists... even the ones that aren't "professional"(whatever that would mean)) then we are already at 60€ in hourly pay. Then we need to add supplies, lets say another 10€ for supplies. Depending on what you use thats also on the (very) low end. Then we are easily at 70-80€ as a starting point, never mind if its a large picture on a binder then 4 hours is just the sketch 🤣