How many times do you hear things such as “I’m sorry but we don’t have availability till next week” or “I’m sorry but the cost is going to be $XXX because it takes Y hours to do that”.
Stop apologizing for being in demand. Stop apologizing for pricing your services properly. Stop apologizing for being good at what you do.
As long as you are providing good service or a good product you should not feel like you have to apologize for charging the proper amount or for not being available all of the time.
Have a great day!