Once you have a name in mind, how do you know if the price is fair? I like to use namebio.com to compare the domain I’m thinking about buying with similar domains that have sold. You can enter the keyword and also use some advanced search features to see a list of names similar to yours, what they actually sold for, and when they sold. You can also research current domain sales on venues like GoDaddy Auctions and Afternic. Finally, Ron Jackson issues a weekly report on DN Journal that covers the top public sales of the week. You can use all these resources to help you price your domains correctly.
In theory, you could technically acquire a domain for $10,000 and be able to sell it for $100,000. You could also acquire a domain for $10 and be able to sell it for $100,000, $10,000… or $100, you get the picture. Because of this, it’s hard to recommend a perfect starting budget because your strategy, experience, and the pace at which you learn will hugely affect your buying and selling decisions.