Cash Flow Confusion… help!

[Haley Parker]

We are about to lease our current home for $3,100 monthly minus our mortgage, insurance and taxes which equals $1,800. So 3,100- 1,800 = $1,300 cash flow 

Granted I understand vacant expenses, HOA, maintenance, capital gain etc will come out of that monthly $1,300 as well.

Because we are moving out of our current home to lease it, we will also be renting space for $1,000 a month (all bills paid) from a family member. Do I also take that $1,000 rent out of above cash flow or no? My thought is I currently am paying $1,800 in mortgage monthly where my next property I’ll be renting for $1,000. Saving us $800 on top of roughly $1,300 cash flow. 

So is my cash flow roughly +1,300 or is it +300 considering my next renting expense. 

Confused if people add their separate property expenses into their rental cash flow or is it all separate? I’m assuming it’s all separate? Hope this makes sense.