NOTE: To some extent my answer is 'US-centric' being as I've never had to price my photography in another country. If you're not in the US, your mileage may vary.
Never, ever base your price on what other photographers in your area are charging. You have no way of knowing what their expenses are, and thus you have no way of knowing what their profit margin is. You can price yourself according to your competition and easily end up making zero profit, or even losing money, because the numbers that your competition uses will not take into account your expenses, your cost of goods sold, the value of your time, etc.! Do the math instead. It's not that hard, and that way you'll at the very least know what your time is worth.
（T + G）* P =報價
T = The cost of your time: how many hours you expect to spend working multiplied by how much your time is worth. Make sure to consider all the hours you will work... Taking pictures, editing pictures, making albums, ordering prints, etc. This is an 'all inclusive' number, and not taking into account all the time you will spend is the fastest way to screw yourself and ensure you lose money on the quote, so make sure to factor in everything and then add a margin, just in case.
G = The wholesale cost of your goods: simple addition of all the goods you are planning on offering your client, and any out-of-pocket expenses (hotel, batteries, etc.) plus the sales tax rate on retail goods, if you are required to pay sales taxes in your jurisdiction.
P = The profit you expect to make: This number should be no smaller than 3, and (unless your client is uber-wealthy) shouldn't exceed 4. These are 'generally accepted ballpark' numbers that are often used for 'quick estimation.' Technically speaking you can throw in whatever number you want, but if you go less than 3 (here in the US) you run the risk of not being able to cover the income tax hit (you are paying your taxes, right?)