You need marketing plan for your new business (also business plan too). Nothing special in selling VPS, this is just one of millions products and service which sell today over the internet. So, you should have a your business and marketing plan which based on your capital, knowledge and possibilities. You may begin with budjet 10 buks per month or 1000 buks per month. Both possible, this is not joke. But you plan should be a changed accordingly you budjet. And of course, 10 buks budjet can't give you warranty that your sales will succussfull (to be a honest 1000 buks also not guaranted this .
When you have plan you should review few company sites which offer same good or services. And correct you plan accordingly, then try research what you can offer new (which not offered yet by anyone) . This is may be some preinstalled software, or free monitoring service or anything else. Generally for getting success on market easist way will be finding you niche or "pack" old goods or services in totally new "advertising" box.
Of course, all of above just common words, but your question is very common too.
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You should make sales and marketing part of your habit if you’re in a very initial stage of starting your business as you can handle it, through managing the cost effective advertisement and your personal involvement.
However hiring new employees is needed and inevitable as you grow your business to certain level.
As w.osama, has already mentioned on his post that he is building a new web site to sell VPS, I guess probably he has no existing customers right now.
I think he is talking how to market it and get the customers, your suggestion is suitable once he get a sufficient number of customers.
However he should focus on local market through cost effective way of suitable ad campaign at this stage.