Make no mistake: You pay a hidden price for shopping at a warehouse club. You race for a parking space. You struggle to navigate the plus-size cart around a maze of merchandise and bargain hunters. You wait in long lines at the register and at the exit as a clerk checks off your receipt. Then you pack the haul into your vehicle as though it's a real-life game of Tetris. Yes, you earn your discounts, one trip at a time.

That's four good reasons right there to like shopping at the warehouse-club Web sites instead. BJ's Wholesale Club, Costco Wholesale and Sam's Club match the low prices at their brick-and-mortar stores with the no-hassle convenience of online shopping (as long as you're mindful of shipping costs). Here are four more advantages to buying your bulk and big-ticket items online:

1. You'll save time and money with valuable online tools and benefits for members only. Whether you're a regular or top-tier member, you'll enjoy online benefits not available to non-members. Pull up previous orders to recall and re-order favorite values, create shopping lists, and submit rebates online to streamline the entire shopping process.

The big three warehouse clubs offer a variety of membership packages. Top-tier membership has its advantages, especially if you're a big shopper. All three clubs' frequent-shopper rebate programs for top-tier members extend to your online purchases.

You'll pay $100 per year for Costco's Executive membership, which comes with a 2% rebate of up to $500 per year on purchases online and in stores. So spend $5,000 in a year and the membership pays for itself. Same goes for the $100 Advantage Plus membership at Sam's. You need to spend $4,000 annually to make an $80 Rewards membership at BJ's pay off.

Non-members can buy items on warehouse-club sites if they pay a surcharge in addition to the listed price. Costco charges nonmembers a 5% fee, Sam's 10% and BJ's 15%. Use price-comparison sites, such as PriceGrabber.com, Shopping.com and MySimon.com, to figure out whether it's worth buying goods from the warehouse club online or going with another Web retailer.

2. You'll find a much wider selection. A warehouse club's Web site typically carries 80% more products than the local store does. Each club has a different approach, so pick the one that's right for you. BJ's specializes in consumer goods. Sam's Club caters more to entrepreneurs by providing special hours and supplies for small businesses. Costco's strategy is to have a smaller inventory of higher-quality products and eclectic items, such as a gray-marble pet urn from R&S Design ($80). "Costco tends to be more creative than its counterparts in the items it stocks," says Michael Clayman, editor of the industry newsletter Warehouse Club Focus. Prices on the Web sites usually reflect the prices you find on items that are sold in stores, plus whatever you pay in shipping costs.

3. You can stock up discretely. We're talking specifically about prescription drugs and booze here, but there may be other products you'd prefer not to be seen buying in quantities of 48 or 96. Though BJ's and Sam's offer deals on alcohol and prescriptions in a number of stores, Costco is the only warehouse club that sells prescription drugs and wine online. In a survey of pharmacies last year, Consumer Reports found that Costco had the cheapest prescriptions. Costco is also the biggest retailer in the world of Dom Perignon champagne. A bottle of Dom Perignon 1999 sells for $120, which is the lowest price we found on price-comparison sites. (Some online retailers sell the champagne for $285 per bottle.) You can only buy wine at Costco.com if it's delivered to addresses in California, New Mexico, Oregon or Washington because of state law.

4. You always have access to warehouse-club coupons online. Each warehouse-club site has a section for items that are on sale that day, no clipping necessary. Among recent offers: at Costco.com, a Hoover SteamVac Dual V Carpet Cleaner for $150, with shipping included; and at BJs.com, a Toshiba 1 gigabytemini-notebook computer for $340 (including shipping). Clubs also send coupons to members directly through mailers and company magazines. Those coupons can be used online.

Caution: Mind the shipping fees. Before you judge the value of any online bargain, take a look at how much you'll pay for shipping. For example, Costco.com sells a Sony Bravia 46-inch, flat-screen, high-definition television for $1,300 to Costco members, plus a $50 shipping fee. You can buy the same set at Amazon.com for $1,240, shipping included. "Shipping costs add to the confusion about shopping online at warehouse clubs," Clayman says.

The sites don't provide you with a transparent way of figuring out how much shipping will cost before you add the item to your online cart -- sometimes the price includes shipping, and sometimes it doesn't. Some coupon offers waive shipping fees. That seems especially true for furniture deals at BJ's. Bigger items and fragile products require additional shipping costs. As is usually the case with online shipping, you can save if you are willing to wait longer for delivery. Unfortunately, you can't save by having the sites ship items to your local store -- they don't offer this service.