I’ve heard lots of horror stories of verbal promises of future equity forgotten soon after.
knowing that you're in a better position than most. The reason is the vendor is two people; they guy who knows he should start the succession process and his other self, the guy that when push comes to shove can't let go because being the owner has become his identity. Almost means you have to chase ambulances for some of these small deals to work. Having the acquisition strategy being the hand off from the old boy is very risky....sure you'll hear about the odd one that comes off without a hitch, but the odds are steep and you can spend years in a situation not knowing.
As general advice, you to need differentiate yourself. how and to who? the more ways the better to improve your odds. For example (key ones off the top of my head, brainstorming would produce dozens more)
1) become indispensable in a business, be the guy who makes it happen and is there whenever need
2) get educated in finance and accounting, its the language of business....if you're illiterate you're at a real disadvantage to try do a deal, especially one that doesn't bite you in the ass
3) if possible, get management experience - even lead hand on second shift, whatever. Showing you've experience in that area will matter a lot
4) if possible, get experience dealing with customers, service, sales, quoting, etc. that's a whole different skill set and is core to any business - business starts with a customer
5) get a nest egg. Live by meager means and save. They guy who has something to put down on a business is head and shoulders above the wanna-be flakes who just want to but never sacrificed.
Why imo this is great advice is all off the above accrues to you. Buying the first one falls through? Your time wasn't wasted and you'll be in much better position to try again.
Aside that you'll need these skills to run the business, the key reason for the above is small deals almost always involve vendor financing and to a much lesser extent bank/angel/whatever financing. Anyone of these investors (the vendor is an investor) is going to be much more confident in taking the risk if you have demonstrable skills in the above areas.
Place you work won't let grow in any of the above areas? move on.
If you do get to a place with potential, force becoming indispensable quickly and work on your education immediately. Raise the subject of your intents early-ish (once its clear how much owner depends on you), find out his intentions and either move on or set some deadlines to get to a deal. Move on when the excuses make the deadlines fall away.
Its not too hard to find small businesses for sale, its really hard to do a deal. Quality intermediaries deal with bigger deals, more zeros, so you end up crappy business brokers who are mostly useless. So you're on your own. imo learning business, finance, how deals are put together is vital, but I'd its the minority that think so as few seem to bother. Some luck out, some don't but the more know, the better will be your odds....that's my message I guess, its a difficult thing and lots of things go into influencing the odds of success. Identify those things and start making changes that better your odds