Forget relying on a listing agent to support why a house should appraise at or above a SC price. Some of them expect an appraiser to do that and will whine and throw tantrums when the SC price is not met.That does not mean they have legit support for it appraising at SC price, they think if a buyer agreed to pay it, it should apparise.
Half the time their "support " are ridiculous comps that have nothing to do with the subject , but unfortunately, buyers can and do base buying decisions on ridiculous comps a realtor selects.
That's why I write, when explaining why a SC price and an appraised value difference, that the parties who negotiate a SC price do so according to individual motivations and not according to the criteria an appraiser uses to develop a market value opinion.
(Truth is, I have no idea how they arrived at their SC price, since I wasn't there and they didnt' invite me to negotiate it.)
Having sold RE once upon a time (for five years), the way parties negotiate SC prices has little to do with the home value and a lot to do with ego, need, greed, fear, financial ability, what the buyer qualified for in a loan, what cash is on hand etc.
First of all, the bid is based on the asking price, and who set the asking price? The genius listing agent. Hmm, house has been on the market a year and reduced three times, the agent really knows the market (cough). Anyway, the bid starts off an asking price, which may or may not be a reasonable, and it goes back and forth from there.
The back and forth often favors which party is more agressive, wants the deal more, has the better agent...till they agree on a price.
Factors that impact price include contingencies, closing date, how much $ down, what kind of repairs, if any are made, etc. And the intangible factors, such as agent skill, stubborness or desperation of either of the parties, etc.
Sometimes the negotiations get ugly, or personal and petty . That is why the best agents have great people skills, not necessarily great valuaton skills, but great people skills.
Successfully negotiating a contract between two parties who frankly may not like each other is difficult, so I can understand why agents get uspet when a deal goes south.
But the agents don't realize that since the price negotiation ofen has little to do with value and a lot to do with placating the parties or compensating for a financial issue, the SC price may differ from the MVO .