When looking at dresses make sure to check the listing to see if it says there has already been alterations, sometimes a dress can only be altered so far. If it doesn't say... Ask. Don't be shy to ask any questions if they don't answer... Don't buy it.
Know the really size of the wedding dress. If you find a dress you love it's ok to go a size or two up but not too far... If a dress has to be altered to much it can really change the look and shape and you may end up hating it! If it is even one size too small don't buy it... It's money wasted, time wasted, don't set yourself up for that kind of disappointment!
When your shopping wedding dresses online remember you need to allow extra time for shipping, possible alterations and delays! If there is even a slight chance it won't make it, don't chance it and disappoint yourself!!!
Be patient and don't settle! There are a lot of listing on eBay, it can be overwhelming but don't just settle on the first dress you think is ok... Find the one that will make you fell as amazing as you deserve to feel!