You do not need to enter anything about being a guest in someone else's home on a tax return. As for what address to use---use the address you want the IRS and/or state to use if they need to mail you a letter or a check. You did not own a home, so skip that. And there is no place on a federal return to enter anything about rent. There are some states that have rent credits--but if you paid no rent, you skip those questions too.
Or----did you and your spouse live in a state that offers a rent credit of some sort?
As far as I know, the states that have anything for rent are Arizona, California, Connecticut, Hawaii, Indiana, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, New Jersey, New York, Rhode Island, Vermont, Washington DC, and Wisconsin.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
