The appraisal is ordered through your bank if you are having financing. If you are purchasing by way of cash, would be the only time you would order your own if you wanted to have an appraisal. When purchasing with financing your mortgage source has their own list of approved appraisers. Even if you had a recent appraisal done on the home, your lender would not be able to use it unless the appraiser was on their approved list. If you are purchasing by way of cash and want an appraisal performed and your offer states such, ask your Realtor. Realtors are a great source for appraisers and other resources for your home.