Don’t Limit Yourself with Boundaries
Boundaries are important for any relationship, and they’re especially important for business relationships. (They’re actually more important for the boundary-setter than the relationship, but ultimately it's the same thing.)
Boundaries can also be very limiting and prevent progress at the same time.
"I don't do work after 6 pm..." but what if I feel like working one day at 7?
Instead of setting boundaries, be objectively honest with each of your actions. Do what makes sense for each scenario as the scenario happens.
Instead of "I don’t do business calls after 6 pm," just don’t answer your phone if it's after 6. You don't have to get mad that someone's imposing on your personal time, and you don't have to stress that you're letting someone down. Just don't answer.
More importantly, if there’s a night where you feel like answering, do it.
One of my biggest mistakes early in my career was setting too many boundaries and being too strict with them. Sure, it probably prevented a lot of hassle, but in hindsight, I'm thinking it caused a lot of hassle, too.