Rights Managed Or Royalty Free When Selling Images

What is the best way to go about this? I know it depends on the situation but if I sell a Rights Managed picture, wouldnt I have to take it off of my site and no longer be able to sell it here? I have a buyer of an image and want to put the best route in front of him. He wants to use it for his company's website (it's a skyline shot of a city)....What is the best way to approach this?