一天多少钱？

Place the phrase at the end of your sentence. You can name the object first. For example, zìxíngchē yītiān duōshǎo qián? (How much is the bike per day?). You do not need complex grammar. Just point and ask. It works for rentals, hotels, or even parking. If you are feeling lazy, just say the phrase while holding the item. People will understand you perfectly.

Use it whenever you are traveling. It is perfect for renting a car. Use it at a hostel or a boutique hotel. It is great for hiring a local guide. Use it when checking the price of a co-working space. Use it at a ski resort for gear. It is a survival phrase for any traveler. Even in a business meeting, you might ask this about equipment rentals.

Do not use this for things sold by weight. Do not use it for monthly rent. That would be yígèyuè (one month). Avoid using it for permanent purchases. You would look very silly asking for the daily rate of a loaf of bread. Also, do not use it if the price is obviously fixed on a sign. It might make you look like you are trying to haggle unnecessarily.

In China, prices are often negotiable, but daily rates for services are usually standard. However, asking yītiān duōshǎo qián is the start of the negotiation dance. It shows you are price-conscious. In big cities like Beijing, rates are firm. In smaller villages, this question might lead to a friendly chat. People appreciate clarity in financial dealings. It is considered practical, not rude, to ask about money upfront.

If you want to be more specific, try yígèyuè duōshǎo qián? for monthly rates. For hourly rates, use yígè xiǎoshí duōshǎo qián?. If you want to sound more polite, add qǐngwèn (may I ask) at the beginning. You can also shorten it to just duōshǎo? if the context of 'per day' is already established. Some people might say zěnme mài? (how is it sold?), but that is more for goods than services.