Prices on Skyscanner always include an estimate of all mandatory taxes and charges. However, the final price you pay for your hotel booking may change because of additional optional extras offered by the provider (these should be optional though). Regarding payment fees, most hotel providers offer a free payment option (usually it’s the most popular card in your country) but they might charge fees for other payment methods. Because you have at least one option to avoid these fees, they don't include them in their prices.