You’ve been waiting years to save enough money to upgrade your kitchen, update your bathrooms – or do any number of renovations. Finally, you’re ready to begin. But anyone who has ever watched The Property Brothers knows that just one surprise—such as hidden rodent or water damage—can bust your budget wide open.

That’s why it’s important to be careful with expenditures, no matter how much you’ve put away for the project.

Here are some planning tips from RisMedia’s Housecall:

Have a budget: True, you might underestimate the costs. But that’s far better than never having a budget in the first place. A budget gives you a concrete number to shoot for and will spark appropriate caution if that number steadily increases.

Save on material costs, when possible: Consider buying recycled or used materials. You might also check on Craigslist, eBay or Freecycle to find cheap— or even free—materials.

Don’t rush: Wait until you can pay cash, rather than using credit. And hold off until there are sales on the major items you will need. “Instead of spending a small fortune for new granite countertops, you can wait for a little while for the materials to go on sale. The same holds true with kitchen island installations, brand-new windows and just about anything else that needs replacing during the home renovations process,” notes Housecall.

Do it yourself: Of course, not everyone has the know-how to complete projects on their own. But if you’re handy, consider tackling the easier parts of a renovation yourself.

Don’t always replace: Reusing materials, such as cabinetry, can save thousands of dollars. Consider refinishing old cabinets for an updated look.

Shop for contractors: Get multiple bids and don’t assume the most expensive person is the best. Do your research to get top value for your dollar.

Sell appliances you are replacing: You may want a state-of-the-art cooktop, while someone else will be fine with your old stove that works just fine. Consider listing old appliances on Craigslist, eBay or the Facebook Marketplace, suggests Housecall.