Many small business owners get into their business and are so focused on starting and surviving they never really think and plan for how they cash out. In these cases it can be very many years later that they start thinking about exiting. Many times the exit is very challenges for all sorts of reasons including debt, ill conceived partnerships, bad/mixed up financials, etc.
One thing that has saved several small business owners I know is the fact they bought the building they use instead of renting. Renting on business start up is usually the only option because of the risk of the business not surviving. At some point though the business is established and cash flows are relatively stable. It's this point of stability that a business owner needs to evaluate how much longer they want to continue with the business. If you feel the answer is 10 years or more you should consider and evaluate how much more in cost purchasing a building as opposed to renting will cost you.
The question is really not too much different than the question of do you want to rent or own your home. You're asking the same question for your business. Although many people are leary of the economy and real estate in general, in many parts, dare I say in most parts, of the country commercial real estate costs are considerably lower than they have been in a long time. If you consider most rents end up being triple net leases, meaning you're pretty much paying all the expenses of the physcial space you can own for not much more than you pay in rent.
Talk to you account and weigh the options. In the end it could end up being your busineess nest egg.