As an abstractor, I have made it a policy to get out work first to clients who pay in full and promptly. It helps that those seem to be the same clients who understand what their client wants and are able to communicate it to me. I always try to get work back within 24-36 hours but, when I have heavier loads, if my client sends only what they can't get online and if they take several months to pay me, their completed searches may take a little longer to get back.