If you have a site of reasonable quality that provides products or services that sell reasonable well, then you should be able to achieve AdWords minimum bids at very much lower levels than $10. (Minimum bids at those levels are intended to discourage sites that are not considered to offer good value to surfers responding to specific ads).
Remember, you onle pay if someone clicks on you Ad and visits your site. Only you will know who much the average visitor is worth to you, and you should bid accordingly. When you start, set your budgets and bids at a level that you can afford to spend and can handle the traffic - then adjust later as you see how things go.
FWIW my ROI averages at over 50%