Hold no stock, buy only when you sell an item and make lots of money! Who wouldn't be interested?
Sadly the reality is very different!
Many leading dropship companies (sadly some that I myself I have joined!) promise hundreds of pounds a week when in reality when you have paid your yearly fee (which can be anything from £9.99-£100+) you find that the vast majority of items that can br dropshipped have an RRP markup of a pound or two. In addition to this, as so many people selling from dropshippers will obviously operate on Ebay the market is absolutely flooded with identical items.
Some dropshippers offer a webhosting and webstore that can in many cases be astronomically expensive, I have seen some for £1500-£2000+ when you can build your own webstore quite simply with many leading hosting companies from £4.99 a month!
Do your research, if a dropshipper is particularly poor then there will almost certainly be many negative comments about them on web forums - it is a good idea to do a search for dropship forums and read up on the company you are thinking of joining before you part with a penny of your money!
I myself have been particularly annoyed to join a dropshipper that showed itself as selling designer watches, clothing, computers and other such goods with markups of £20-80 only to pay the joining fee and see that these items are NEVER in stock - I have learnt from this and will never join a dropship programme without ringing or emailing first exlaining what it is of theres I want to sell and make an understanding that if it is consistently not in stock that you will expect a full refund on any membership fees paid.
There are a lots of dropshipping cons out there but do your homework, find a good product that you know about that has a markup worth reselling and you will soon be in business!