Walk across the street from your house, turn around, take a good look at your yard and ask yourself if you're impressed by what you see -- or just plain depressed. We can't all have yards worthy of being on the cover of a landscaping magazine.

Those yards generally come with a high price tag. But a little cash can go a long way to improve your home's curb appeal. In fact, with existing homes selling at the slowest rate in a decade, if your house will be on the market, you can't afford not to spend some money and time on landscaping that will distinguish your house from others.

So we asked landscape professionals how homeowners could get the most bang for their landscaping buck within certain budgets: $100, $500, $1,000 and $2,000. They even threw in a few ideas for ways you can improve your yard without spending a cent.

Regardless of your budget, before you grab a shovel or head to a nearby garden center, you need to determine your goals and ask yourself some questions to ensure your money is well spent, says Tara Vincenta, founder of Artemis Landscape Architects, in Brookfield, Conn.

Are you trying to improve your yard so you can enjoy it for years to come or to increase your chances of selling your house? Do you live in the city, 'burbs or countryside? What is your home's architectural style? Do you live in a wet or arid climate? Are deer or other wildlife an issue? "All these considerations can affect your approach," Vincenta says.

You don't want to waste money on plants that require full sun if your yard is in the shade. Nor do you want to try to replicate that cool, modern landscape design you saw on TV with your Victorian home -- especially if you're trying to sell it. The kind of person who would be interested in your home would want a garden that complements it.

"Do research before you go to a garden center and buy at random, or you'll end up with a hodgepodge," Vincenta says.