This is really a personal question that will need to be answered by each owner individually. Believe it or not, we have had some sad situations come about where the owner did not think there was any value in their practice? This could not be further from the truth, your practice is an asset and you should take full advantage of that when the time comes to hang it up. When committing to sell your practice, you should be aware that most buyers will expect you to stay on and assist with transitioning the client base. Typically, you should allocate another 45-60 days or transitional assistance for smaller firms. Larger firms will include more time and possibly up to 1 year.
When exploring your options for retirement or selling the practice, there are really only 2 options: Sell or shut the doors. Do not underestimate the fact that there are potential suitors out there that want what you have, a book of a reoccurring revenue stream.
If you choose to sell your practice to an outside buyer, plan on having current financial information available as well as availability to stay on and assist with transitioning the client base. Do not expect to the practice to sell and the process to be over in a matter or days or weeks. Typically, a practice will close from start to finish in a matter of 3-6 months for small to medium size firms and closer to a year for larger firms.
When the time is right, be sure to allocate another year or so in the equation. If you plan on moving to somewhere warm, plan on doing it 6 to 12 months after your original target date.