It really depends on what it is. The MBAs would do a market analysis to figure out what size the market is.
Say you came up with a new castration tool. Your potential market is the number of folks who do their own castrations plus vets. Figure what you can make it for, what you can sell it for, and you have your potential profit. If it's a small market, there may not be anybody else interested, and the cost of the patent may not be worth the potential income. If the most you could make is $40,000, the $10-15,000 for the patent might be a waste.