Negotiation Assistant Introduction
Negotiations are, in general, a farce. Their primary purpose is to let both people fool themselves into thinking they got a better deal than the other person, so we go through the motions: one person makes an offer, the other counteroffers, they both provide plausible-sounding arguments for why their price is more fair than the other's, and eventually they meet somewhere in the middle. The outcome is almost entirely predictable; both people had a decent estimate at the beginning of what the final sale price will be, but if either of them had made that their starting offer, the other person would have tried to negotiate it further in their favor.
This wastes time, it can lead to bad feeling, and it rewards dishonesty and manipulation. There's no perfect way to avoid these issues, but this webpage is an attempt at an alternative system. The buyer and seller each input their best guess at a fair market price for the item, along with what they personally value it at. The site does a bit of math and gives them a final price for the item that's fair to both people, without revealing how much the buyer was willing to pay or how low the seller was willing to sell for. It's quick and painless, won't lead to arguments, and prevents people with poor social skills and self-confidence from being pressured into accepting a worse deal.
The way it works is simple: If the lowest the seller is willing to sell for is higher than the highest the buyer is willing to pay, no deal can be made. If that's not the case, then a deal can and will be made. The final price will take into account both parties' guesses as to a fair price (along with the chance that they're lying or mistaken) in order to estimate a price that's equally fair to both. This accomplishes the exact same thing as a normal negotiation, but without all the downsides.
As long as both parties agree in advance to abide by the result, this system means that they both have an incentive to enter a number that's close to their honest valuations and not try to trick each other. Inputting a dishonest fair price has the same downside as doing it in a normal negotiation; the other party will get mad at you and accuse you of trying to rip them off. And inputting a "best price" that's less than you'd actually be willing to pay (as the buyer) or more than you'd actually sell for (as the seller) makes it more likely that the deal falls through and no sale is ever made at all.
For the technical details, see here.