xiǎng bù xiǎng zuò dōu kě yǐ, dàn zuì hǎo xiān wèn qīng jià gé hé shì fǒu bì xū

想不想做都可以，但最好先问清价格和是否必须。

Whether you want to do it or not is up to you, but it's best to first ask about the price and whether it's mandatory.