A: The required time between a Ch 7 and a Ch 13 is four years, so you're OK there. And, since there is no requisite minimum payment and, as long as $80 is your disposable income, there shouldn't be a problem there. Also, most trustees require that any amount over a specified amount of tax refunds (possibly IRS & state combined) must be remitted to the trustee for distribution to creditors.
If you can speak with an attorney in person before filing, do so.
A: Your questions have nice Black and White answers. Yes, you count the amount he gives you for rent in Schedule I and, no, his income is NOT included in calculating the Means Test and, no, he does NOT count for household size.