The US government incentivizes business owners to do three things: own property, create jobs, and buy equipment. This is obvious from the tax code.
Not surprisingly, developing an eventual exit strategy involving those three things can put you in a very comfortable position.
1. Own the building you're in. It'll make a huge difference to your asset sheet. If you play your cards right, you might own the entire business park by the time you retire, and all your neighbors will be paying you rent. The US government incentivizes commercial property ownership through low interest rates, SBA-backed lending, tax deductions on interest and building depreciation, and perpetually deferred capital gains taxation through the 1031 like-kind exchange rule (in fact, the tax basis resets at the time of death to FMV, with no capital gains owed by your heirs).
2. Hire and groom great employees, and pay them well. A potential buyer wants a turn-key and won't be interested in shops where the owners are still heavily involved in the day to day. Also there's a high likelihood that your eventual buyers are the employees themselves. Even if they might not have the capital up front, you could seller-finance the business to them over several years. You could even negotiate to retain equity and collect dividends (double dip) even after you've been fully bought out. Don't sell the property though, keep that for yourself.
3. Tax rules favor trading in used equipment for new. Also, customers like working with shops with new equipment, and buyers like buying shops with new equipment. Plan your purchases with resale in mind so that you can keep your core (bread and butter) equipment fresh. This is all in addition to the most obvious benefit, which is that new equipment generally means higher productivity and less down time.