Pam Erman directly addresses camera:  Strong seller markets nationwide over the last couple of years have programmed most sellers to expect their homes to sell at top dollar in less than a week. While that could still be a reasonable expectation, the key is to provide data-backed advice regarding market time and pricing in your local market.
I'm Pam Ermen, a seasoned real estate professional and coach with Real Estate Guidance Inc. in Virginia. Let's take five minutes to talk about the market trends you must know and how to guide sellers through the process by shifting your skill sets to match your market.
Sellers may be influenced by NATIONAL market trends that don't reflect their LOCAL market conditions. Consider it time well spent educating your seller about the distinction between the two, then provide them with data backing up your findings. The confusion created by a changing market is an opportunity for you to earn trust as the market expert.  
To do this, understand the interaction between supply (which is represented by the number of available market listings) and demand (which is represented by the number of sales that have occurred.) Even if buyer demand drops and listing inventory is non-existent, you can expect home values to remain strong and market time to remain reasonable.
Some of the best sources to find this data include your area's MLS reports and Florida Realtors SunStats, an interactive market data program. It can help you prepare a listing presentation showcasing market data and enable you to manage seller expectations from day one.
Here are some other specific metrics you'll want to research before speaking with potential sellers:
First, study previous sales. Check factors like days on market, sold prices, and the list-to-sales-price ratio. Did the final price still exceed the list price? Did it sell at list price, or is the price starting to become a negotiable point between buyer and seller?
Next, identify the "pent-up" demand in the market. This is the existing buyer pool waiting for the next suitable property to come to market. This is your greatest window of opportunity for maximum interest and multiple offers. If multiple offers are possible, this is where and when you'll find them.
In a transitioning market, check a sold property's history for price reductions and any current listing that has been reduced since its original list date. Is this activity increasing in frequency?
If you're the listing agent and the market shift includes an increase in the average market time, make sure you're reducing your price slowly. With smaller buyer pools, once you've cleared the pent-up demand, it may take a little longer than you're used to before the next buyer enters the market. If low inventory also exists, selling for the original list price weeks after listing may still be possible. Let your market knowledge and not just market time determine how you counsel your seller about their price and potential reduction.
Remember to watch the BASIC economic factors in your market, the early warning indicators that tell you how your market may change. Tracking factors like unemployment rates, interest rates, mortgage availability, and housing affordability all help you assess your market's overall health.
One last suggestion: It's been a while since many agents considered the cost of owning vs the cost of renting. Look at how purchasing at today's rates compares to the aggressive rent increases most tenants are experiencing.
Successfully managing a seller's expectations in today's market demands a deep understanding of market dynamics, data analysis, and the ability to communicate all that you know effectively. With this data, you can confidently guide your clients through any real estate landscape.