|This is going to be more of a negotiation than a calculation.
It all comes down to money. Either they have it and are used to spending it - or they don't. Some companies can talk a big game only to cheap out when it it is time to commit. The graphic arts world is full of anecdotes of companies spending 1000s and 1000s and 1000s of dollars on logos and other companies balking at spending $100 on something as critical as their principal visual ID. Before you get started, you need to get a handle on what type of entity you are dealing with.
* Is it a public corporation, a large privately-held business, or a small business?
* How many employees?
* How much annual revenue?
* How much is their annual marketing budget?
* What is the scope of their marketing? (Print, collateral, business cards, channel advertising, social media, etc.)
* Are you dealing directly with the company or with the agency doing their marketing?
* Is your image something they could replicate without running into visual plagiarism issues?
It really does come down to money - your money! This is a business transaction, not an ego-boost. They either pay to play or they don't get your image. And they should pay as much as they can. If Bob's Bike Shop has one other employee besides Bob and is doing $150,000 a year gross while spending $5000/year advertising, and his new logo is his first update in 15 years, then maybe $1000 might be both reasonable and a stretch.
On the other hand, if it's a multi-million dollar business that spends millions a year on advertising, maybe $50,000 is way too little. If it were me, if the company has more than 15 employees and any degree of public visibility, and if I felt like they really wanted my images, I would go to Wonderful Machine and pay them to help me both with the pricing and negotiation.
Sure, it's always nice to get the inquiry, but you owe it to yourself, your family, and the industry not to devalue the work.
You may end up needing to offer a structured payment where they can pay an annual licensing fee if they can't afford to pay the whole thing upfront - and that will mean drafting an ironclad license that protects you.