Listed property price v.s. transaction price A house may be listed at a certain price (e.g. £200,000), but sells for a different price (e.g. £210,000).

In terms of economic theory, how does the transaction price tell us more information than the listed price?

Most papers use listed price because of data availability, and then state that it is more preferable to have transaction price. Why is this the case?
The listed price tells you something about the expectations of the vendor and their estate agent. It's a leading indicator, hinting at where the market may be going next.

The transaction price tells you something about the actual market during the period of the sale, in the period between the property going on the market and the date of exchange. It represents a real meeting of supply and demand - it is a market price. It only becomes available in the weeks or months after completion of the transaction, so the market will already have changed by the time one can get all the data.