When acquiring rare gold coins it is important to understand the difference between sight-seen and sight-unseen coins. If a dealer attends a coin auction and fifty 1903P $20 Liberties in MS63 are up for sale, a dealer may make a bid on those coins sight-unseen. This bid will typically be much lower per coin than if that same dealer were to be able to sit with each coin and examine them. This could be a difference of hundreds of dollars bid on each coin, even when the grade is the same on every coin.
Nicer coins fetch more of a premium. If a customer wants the cheapest coins available, he or she can expect the lowest quality coins. The better the quality the more money a coin will cost. In other words you get what you pay for.
For better dated rarer issues, these coins do not trade on a daily, weekly or even monthly basis. These types of coins trade when a buyer and seller get together. A dealer will pick up that particular coin sight-seen and turn around and retail it to a customer sight-seen. This coin will fetch a higher price than a sight-unseen coin. This coin would be something that a collector would be proud to own and that the dealer would want to buy back at a later date.
Sight-unseen prices do not represent value; they represent quick-sale wholesale prices. At an auction one might see sight-unseen bids at around $1,400 on a particular coin and yet the sight-seen bids may be in the area of $1,700-$2,000. Therefore sight-unseen bids would be taken when a dealer needs quick money. When a dealer sells nice coins they command sight-seen prices. These coins are of the highest quality and thus command the highest prices when being sold back to a dealer. When a dealer knows what he or she sold to a customer sight-seen, he or she should be willing to buy them back at the same level of quality.
What is important to understand is that some companies will sell coins at sight-seen prices but then buy them back at sight-unseen prices. This could mean hundreds or even thousands of dollars based on the coin that is being sold back. Therefore it is important to choose a dealer that will buy coins back at sight-seen prices.