My assistant's husband is a graphic designer. They both offered to have him design my invitations for free. Because she's my assistant, we don't spend time with each other socially outside of work. However, I do feel a little weird having her husband do the invites and not extending her an invitation. That also opens another can of worms though. I was only planning on inviting the one co-worker I'm close to. If I invite my assistant, I then have to invite the controller. We're a very small company and word would get around.
I could decline assistant's husband offer but it would save me a ton of money.