How much do you know about setting up your own site or sites? Will you be doing this or hiring someone?
If you are doing everything yourself, pretty much all the money you need to spend will be on website hosting and a domain. That will be about $75 for the year.
There are some tools you may or may not want to spend money on to help. Things like an article submitter. That will allow you to submit articles to hundreds of different directories and gain backlinks to your site. It is a huge time saver.
You can find some of these programs fairly cheap.
Incansoft (I'm not an affiliate, just a big fan) has some fantastic software for very reasonable prices. They are having a sale sometime the end of January. Most of their software will be on sale for $12 or less.
Their ArticleBot, SocialBot, and RSSBot are invaluable tools to me.
Just my opinion though. Lots of people do very well without using stuff like this. For the time they save me, I wouldn't live without them.
And I would be careful about spending too much money before you have a good grasp on what you're doing. As money starts coming in, reinvest it into your business. Find tools like I mentioned above that will let you scale up what you are doing without spending more time.