It is different from bowling alley to bowling alley but I have seen prices of bowling shoes from 5 bucks for the time you bowl to less than that during times where not a lot of people bowl. Like at night time during the week, renting bowling shoes may be cheaper than on a weekend when the prices of bowling tend to be higher.
On weekends, Friday and Saturday nights tend to have higher prices for bowling with games, food and renting bowling shoes. If you know you will be bowling one than once or you will be bowling more often, than I would buy your own bowling shoes for yourself to save some money and bowling shoes do not cost than much money and the shoes can last a long time over time. I have had my bowling shoes over 3 years now and I bowl once per week so it has saved me a lot of money over time.