Cloth diapers and disposable.. how many should i buy?

Sarah
Sorry for this silly question but i'm shopping for what baby needs and i plan to try and mix cloth diapers and disposable ones as i think it helps in the costing. I'm a stay at home mom so i dont mind the cloth diaper. So how many cloth diapers should i get for the first time? 5-10? Do i need to prepare anything else like a special laundry detergent for the diapers?