When Selling always avoid the Make offer.
1. it confuses the buyer - how are they supposed to value a domain? Rarely do they have experience.
2. they will always play it safe and the difference between your expectations and theirs will be far greater.
Educate them, exacts, competition, Google favours keywords, % of potential traffic for long and short tail keywords, likely ROI in what time frame etc offer SEO, examples of recent sales, market value in accordance with current climate.
Then let them know that no bids considered under £...... if they come back with an offer you now have opportunity.
Keep their records, next year they could have grown or have a new marketing manager. New opportunity!
Educated & Expectations completed.
I have a few signatures i use and just fill in the gaps.
I always follow up and as long as there was no definite no it is still a possibility for the next time you get an offer.
A new offer comes a long and you mail the first guy just to let them know that you are in talks with a new buyer. "Just a polite follow up"