How do you bracket a 6 acre parcel when the nearest comp is 14 miles out?

The two sales inside 4 miles are the whole argument, so the ROV lives or dies on whether you can hand the appraiser the closed price and not just the address. In a non-disclosure state you may not be able to, since roughly a dozen states don't put sale prices in the public record at all, and then you're relying on the appraiser's MLS access or the listing broker being willing to confirm in writing. Check which kind of state you're in before you spend a day on this.

The other thing I'd look at is the time adjustment with no support. Most ROVs I've seen get rejected because the requester argues value instead of pointing at a method problem. A line that says "the market conditions adjustment is applied without a stated derivation" gets read differently than "I think it's worth 148."

On timing, an AMC-routed ROV usually goes lender to AMC to appraiser and back, and each hop has its own queue. Ten days is optimistic in a rural coverage area where one certified residential appraiser is covering four counties. Ask your loan officer what the lender's stated ROV turn time is and get it in writing, because if it's 15 you're making a lock extension decision, not a value decision.

The shop at 6k I would leave alone. Support for outbuilding contribution in a market with 90 sales a year is genuinely hard and it's the weakest place to plant a flag.