Buy or rent a server in a datacenter for x amount of dollars.
If you go this route, you must be prepared to monitor your server or servers 24/7, and pretty much be prepared to give up your life.

During this time, it’s necessary to make sure the server is locked down security wise, firewalls are working, sites are up, mail is working correctly (and pray it doesn’t break because if you do have customers you’re up the creek until you get it fixed), and go about blocking hackers if need be. When a bell goes off because something goes wrong, you must drop anything you’re doing (including sleep) and fix it – and stay awake til it’s fixed.

You must also be prepared to answer and fix customer issues and do some handholding.

There’s alot more involved, but that’s the gist of it. Of course, you can hire a sys admin – a good one is only $80,000 a year or so, but he/she won’t want to work 24/7 for that, so of course you’d have to hire another one. Then, you’d need a tech person to answer the phone, answer emails, and fix problems the sys admins don’t want to fix. Then there’s sales, billing…

Or, you could always go for a reseller account, but this has it’s responsibilities as well. If something breaks on the server, you don’t have to fix it, but if you’re a good reseller, you still need to be on top of things and field calls/emails for your own customers. Some hosting companies that have resellers will not speak to your customers (and that’s as it should be) so it’s up to you. You’ll still need to be able to fix issues and do a certain amount of handholding.

It’s not easy.

-you need a server (or maybe racks of servers)- obviously you need a good one that can handle a huge amount of data
-you need to lease a significant number of domains.
-a very fast internet connection – you might want the t3 to t1 connections.
-softwares – servers(microsoft server, linux etc), security(antivirus, firewall, etc.), database(sql, iis, etc), and all that stuff

2.) For your second question; there are different ways to store your website files,
-if you would use your own computer you must have a static ip address provided by your isp.

http://www.bluehost.com

I paid $5.95 a month (a deal they had a while ago. I also prepaid for 2 years) for unlimited bandwidth, unlimited storage, free lifetime domain, and it has a lot of tools such as easy WordPress and Drupal setup. From what I can tell, they support almost anything a website could ever need. If anything, you just might want to write your own HTML/CSS/PHP.

Check the features

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