Sandra, If you are paying cash an appraisal may not be needed. If you are financing the finance institution will order an appraisal to determine if the risk of loaning money is a good deal for them. Costs of appraisals are going up drastically because of the short supply of appraisers and big demand for their expertise.
I agree with Shelly at RE/MAX, and unfortunately most often you will be paying for the appraisal in advance. In effect you wont know the market value until that appraisal is done. There are a few online tools that can estimate value, but the appraiser will take more into consideration than the online estimates. If you are working with an agent, chances are they have access to tools to let you know if your close. If the property doesn't appraise, you can try to renegotiate, however every deal is unique to its parties so no way to know going in. Lean on your agent for help on this.
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