Phrases like “I’ll have to” or “find the time” or “make time” tell your client a few things: He/she is a burden to you, and working to help him or her is not your main goal.
It shows that you don’t really like your job, or at least, you don’t like the part that involves talking to the client, and would prefer to be doing something else. What you say can have a huge effect on how your client views your, whether intentional or not.
Saying that you’ll be “glad” to do things for clients or that it would be “my pleasure” shows you’re ready to and willing to do the work. Try to use those instead.