Yes, an agent can run comps and you can hand them to the appraiser, but the appraiser decides which comps get used. Treat the agent's work as helpful input rather than the final word. An agent's opinion of price can also differ from an appraised value, and that is normal: a realtor is estimating what the home would realistically sell for, while an appraiser is bound by comparable sales data and documented adjustments. Both are useful; they answer slightly different questions. One guideline point worth knowing. A licensed appraisal is generally required on a refinance unless the automated underwriting system offers an appraisal waiver, and only conventional loans have those. Fannie Mae calls it value acceptance and Freddie Mac calls it ACE, and the system grants one only when its confidence in the data is high, which tends to show up at lower loan-to-value levels with more equity cushion. You cannot request one, and FHA, VA, and USDA have no equivalent waiver. FHA Streamline and VA IRRRL refinances skip the appraisal entirely, but that is a built-in program feature, a different thing. Waiver eligibility changes over time, so confirm current guidelines when you are in a live loan.