I'll break down my situation and my questions so I can get clear answers.Situation:I live (rent) in Los Angeles and am looking to purchase a home to live in. 

If you do it right you can live rent free or maybe even cash flow a bit positive.

I too am in a very similar situation as yourself, I just live/rent in San Francisco.

Where I live rent wouldn't even cover PI.

I am also an Astoria local (though I’m a transplant) looking to get started in REI.

I have the following choices I feel below. 1. move to Philly (which i will soon) and buy a 2 or 3 unit property to house hack with the hope of getting 4-6% cocr after moving out from one year living in one of the units. 
2. purchase a townhome in Philly and airbnb it 
to cover all cost + cash flow left over3. purchase a single family house and rent out the rooms in Philly to break even. 4. purchase a 2 unit in Clifton NJ and have my family all chip in to pay the mortgage living with free from paying (a not good idea long term + family already does this in a one family house in Paterson which they don't mind ) 
what i am looking for is 1. to house hack so i can cash flow after living there for 1 year and or break even. 2. force appreciation with light rehab done to the units3. in a C or better class areaI would be doing a conventional loan as i do want to do fha since rates are low now trying to see which method would yield me to cash flow / live rent free with some cash flow. i read many books and all say you profit when you buy so i want to buy right. i can buy up to 420k and currently no debt. 

i would be doing a conventional loan as i do want to do fha since rates are low now trying to see which method would yield me to cash flow / live rent free with some cash flow. i read many books and all say you profit when you buy so i want to buy right. i can buy up to 420k and no debt. what method makes the most sense? 

My mother in law right now is under the care of her son in San Francisco, She has liver cancer, too weak to travel, so we doubt she'll ever return to her coop.

I was thinking of maybe buying a condo or duplex next that she can rent from me for a very low price or live rent free when she is older.I am just trying to help my mother find a way to have her money work for her.

option 1 mortage                                                     3508 monthfront house potential income                2950 monthdifference                                                     $558  month expense to live in 1 bedroom ,currently paying   1858 monthless potential           558 month  savings of               1300 month, x 12 months  = 15,600 annual savings toward the next investment.this is a payout of  558 x 12 = $6690 year Option 2 rent front house     2950 rental incomerent back house      1650. rental incometotal rental income   4600, monthless mortage              3508.positive cash flow     1092.00 month. x 12 months  = 13,104 positive cash flow income. option 1now take that 1092.00 month toward another purchase  in that less expensive market and live rent free....option 2 or use to drop rent at preexisting house 2020.-1092.= 928 rent and two others are paying off your home . that is the options I see in 15 minutes of planning.