When you're starting out, if you don't have much of a budget, use your time in place of the money you don't have. It's easier to buy just a few high priced names and sit on them as an investment since you're only paying reg fees on a few names, but when you're registering names to resell, you not only have to worry about recurring reg fees if you don't sell within a year, but you also have to work harder to sell them vs. higher end names where people often come to you looking to buy them. Use your time to do as much research and looking up of names as you can and get only the very best so that your portfolio isn't hit-and-miss. After enough experience, the time you spend to research will dwindle and disappear as you will have wisdom from the experience.
I started out low and now have a condo and a steady domain income to show for it. You CAN succeed starting low, but like anything else, it takes hard work. It's better to act as if nothing comes easy, so that if you manage to be lucky, it's icing on the cake vs. something you need.