There's no simple answer to this question. The “best time” to buy a home is usually when fewer buyers are looking. There are two terms that you should be familiar with: buyer's market and seller's market.
A buyer's market exists when there are more properties for sale than there are buyers. In a buyer's market, sellers may be more flexible and willing to work with a buyer. A buyer has more time to check out a property and make decisions.
A seller's market exists when there are more buyers than properties for sale. In a seller's market you must be ready to act quickly. During a seller's market, sellers typically may not be as flexible or as willing to negotiate a lower price.