Invitation Addressing - Help Please!

Do you write out the 'AND' on the envelope.. or does it not matter.
Ex:
Mr. & Mrs. John Smith
or
Mr. and Mrs. John Smith

Also, do all single guests get invited with a guest? I have some cousins over 20 that are single... do I invite them with a guest if they are not dating anyone?

And, last but not least, if you are inviting single female guests, do you address it as:
Miss Joan Smith
or
Ms. Joan Smith

????? Help please. I need to get my invite list in order and off to the calligrapher asap.

TIA!

I would spell out the word and.

As far as inviting singles with guest's, if your can afford it in your budget I say yes invite them with a guest.

Single and divorced female's. Use Ms.

I use Miss when the person is younger

Sounds good. Thank You for the info!

I use Ms. for anyone over 18, Miss for younger.

I'm inviting all of my guests with a date, but that's something that you have to figure out on your own. Whether it's something you can afford. If not, maybe invite those people with a guest who are seriously seeing someone. Although 'seriously seeing' might be difficult to define.

Lastly, I would spell out 'and'