> That is, when a large client I work with called me with one-off requests, I usually just fulfilled them. It made me look helpful and not standoffish, helped our relationship
Until it becomes a pain when your client stops recognizing it as favors and perceives it as your obligation. Being the nice guy can come back to bite you in the ass.
Maybe, but I've never experienced it myself, which is why I still do it.
It's worth pointing out that the work isn't really free. I still include the changes in future quotes and mark them as no charge to remind him what I did. This gives me leverage in negotiating fees on larger changes.
Until it becomes a pain when your client stops recognizing it as favors and perceives it as your obligation. Being the nice guy can come back to bite you in the ass.