Every person has their own way of BIDDING, SNIPING, BIN (Buying It Now), or WATCHING.  As both a Buyer and a Seller, I've experienced each of the different ways and while I'm not an expert on any particular way, I do see many of the Pros and Cons.  This guide is nothing more than my opinion, but I think it's a reasonably educated opinion.  Here Goes...

BIN or BUY IT NOW

BIN is an easy way to shop.  Many sellers use the BIN price to let their prospective customers know how much they hope/expect to get for an item.  This is a simple option if you know exactly what you want, know the actual or approximate retail price, and/or want it now.  The PROS of BIN are that you don't have to wait until an auction finishes, you know exactly what the cost is going to be, you aren't competing against other buyers, and you'll get your item quicker than if you waited for an auction to end.  The CONS of BIN are few, mainly that if you bid or watch it until the end of the auction, you may get it for much less than the seller would like to get for the item.

SNIPING

OH YES, Sniping is a fact of life on eBay and many other auction sites.  Everyone proclaims to hate the snipers, but almost everyone has tried it themselves in some form, whether executing a Perfected 'last second' Snipe with your first and only bid, or rebidding in the last few minutes (yes, that would be considered a 'friendlier' form of sniping too).  Perfected Sniping is essentially waiting until the final second of an auction and not giving other bidders a chance to rebid.  I curse snipers when they beat me out of something, but it's really my own fault (we'll get into that under BIDDING).  The PROS of Sniping are outsmarting your opponent and getting what it is you wanted without battling midst rebids from others.  The Sniper is usually someone who has weighed the pros and cons of BIN and believe they can get it cheaper by waiting.  The CONS of Sniping are that in some instances you end up paying more than if you had BIN'ed it.  You can be beat out of an item easily, even if you're good at Sniping, if bidders have bid as eBay suggests (we'll get into that under BIDDING).

WATCHING

You see an item you'd like, but you're not 100% sure if you're going to bid.  So you WATCH THIS ITEM.  I love the concept if that's all I'm doing.  As a seller, I love folks who Watch This Item, because it tells me that I may see some battle bidding in the last hour of bidding, and that I am more likely than not to sell the item.  PROS are that you can watch an item for the length of the auction and check the listing frequently and easily from you My EBay page.  As the Seller or Potential Seller of a similar item, you can watch what the competition gets for their item before listing yours.  CONS are a bit different here because the Buyer is at a bit of a disadvantage.  The Seller can have a 'Hit' calculator that tells everyone how many people have looked at the item, but the number of Watchers is seen only by the Seller.  I recently sold a Gucci bag where the 'Hit' calculator registered in the high 400's.  Thing was, the WATCHERS numbered relatively high as well.  Each WATCHER figures to bid closer to the end of the auction, but if all the Watchers bid near the end, they themselves would be driving up the price without realizing it and not understand why so many others were bidding against them!  The biggest problem with being a Watcher though, is missing the end of an auction that you really did intend to bid on.  If I had a nickle for every auction I missed like that... 

BIDDING

eBay recommends that when you find an item you want, bid on it when you see it.  Calculate what the highest amount you're willing to pay is and bid it when you see the item right at the get go.  The only CONS to bidding this way is that some folks think they draw more attention to an item by bidding early, therefore inviting competition.  Not So!  PROS include never missing out at the end of an auction because you weren't sitting in front of the computer.  That's a huge Pro.  PROS also include setting YOUR amount early, before the 'Heat of Battle' sets in.  I know that I will sometimes bid much more than I planned in the last minutes of an auction because I get caught up in the competiveness of it.  Another PRO is that Snipers will have to pay more to get the item even if you don't win (kind of a win-win don't you think? LOL);  you'll actually win more often than getting Sniped.  I learned this lesson in December as I hunted for an outfit for New Year's Eve.  I found the ABSOLUTELY MOST PERFECT DUSTER BLOUSE COVERUP OF ALL TIME.  I 'WATCHED' it for 4 days before bidding just a dollar over the minimum bid, mistakingly thinking no one else would bid.  RIGHT!!!  On the last day, I watched it most of the day, but had to leave to go pick up my son from some sports thing.  I figured I'd be back in time just in case someone else decided to bid.  Instead of increasing my bid (or had I placed the original bid at the $30 I WOULD HAVE / COULD HAVE / SHOULD HAVE PAID), I left to go get my son.  I got back with about 3 minutes to go.  Still no other bids.  WOW!!!  HOW LUCKY AM I?  Fast forward to 3 seconds before time runs out, and OMG, suddenly there were 5 bids and no time left.  What I couldn't see was the WATCHERS and potential SNIPERS.  I didn't even have time to rebid.  My beautiful, perfect, best duster ever went to the Sniper for $19!!!  Had I bid the way eBay recommends, I wouldn't have been cussing at the Snipers right then, and myself later!!!  It was my own fault for not bidding $30 in the first place.  I still wouldn't have paid more than the $20 (see automated bidding below), and I would have had some padding.  I would have gladly paid $30 and should have bid accordingly.  I didn't follow eBay suggestions on bidding and lost out.  Plain and Simple.  Now someone else is wearing my Duster!!!

AUTOMATED BIDDING

This is really just for the new eBay Buyer, as seasoned Buyers already know this.  If I had bid the $30 I was willing to pay for the duster in the very beginning, I probably still would have only ended up paying $20 for the duster.  The duster started out with a minimum bid of only .01 and that would have been all I paid if no one else had bid.  If someone else had bid $5 after I bid, my bid would have still been higher, and the bidding would only show $5 because I bid at least that amount first, even though my maximum bid would have been $30.  With automated bidding, you'll still only be paying a few cents more than any bid lower than your max, until someone (may or may not) bids higher than your max bid.  Your max bid doesn't show to anyone, not other buyers, not the seller, not anyone! 

SO, THERE YOU HAVE IT, my opinions and thoughts on the PROS AND CONS of Bidding, BIN, Watching, and Sniping.  I hope this gave some insight into the Pluses and Minuses of each form of purchasing.  If this guide was of ANY help whatsoever, please take a moment and check YES below. 

~Thank You For Reading My Guide~