Buyout angel investor to avoid exiting?

It appears that in order to raise angel investor financing for my first-of-it's-kind product startup ($500K+ minimum) I will have to give up the whole dream within a few years in an exit event.

Obviously, if I had the funds personally, or had family or friends who could help, I would be able to retain ownership of the venture that I've worked on for over 15 years, am so passionate about, and could expand it's product line into relevent market segments and foreign markets and make it a career. (I'm 53.)

The product will be marketed to remodeling, painting, construction, and maintenance companies as well as apartment complexes and building and facility maintenance departments - so it is not a mass market product line and has limits on the scalabilty meter. It will accumulate a couple hundred million gross sales over 10 years if no copycat competitors enter and take a piece of the pie. Even if they do, I will lead in the market.

Before I start making pitches, is there no legitimate, above-board method to satisfactorily buy out an angel investor and ride my vision for all it's worth?

It's not clear what's going on here. It sounds like you're considering accepting an angel investment that requires you to have an exit event within some sort of timeframe. Frankly, that's a bit aggressive for an angel--they're typically more willing to wait for a while. So, you may want to ask yourself if you have the right investor.

In any case, of course there are legitimate ways to buy-out the angel investor -- just offer to buy out his/her shares and negotiate as to price and how to pay for it. If you don't have the cash, then perhaps he/she will let you pay via debt.

You might even put that right in as part of the investment documents -- if the board decides at the time that an exit event is not in the best interest of the company, then the company can redeem the angel's shares at a set price.