It's nice to see that a family friend that's a lender mentioned shopping around for rates so that you can find the best deal possible, even if that means not working with them.

I'm thinking it's better to rent the entire property vs a room.

While you save, home prices could continue increasing too.There's always opportunity cost with buying today or waiting but I recommend doing what's best for you.Yeah I want to get in ASAP (as long as it’s financially possible of course lol), I’ll explore my options and go from there if my calculation will be beneficial 😅 

But I just wanted to know if it possible to own 800+ properties or close to it by 30?

I am also a natural introvert, but have learned that putting myself out there and getting uncomfortable is a skill.My biggest suggestion would be to go to as many local in-person meetups as possible and find the people who are "moving and shaking" to become friends with them. 

If possible I would want the amortization over 25-30 years.I know cash out refi is quite expensive with the origination fee and everything, early pay off could cost too or drive the rate up.

Is that even possible? 

Determine how comfortable you are with these risks and make sure you have enough money saved up for any unanticipated difficulties.Examine Market Conditions: Do some research on the local real estate market as well as those of other possible investment destinations.

Wanting to convert older properties to newer, better locations, if possible.

When reviewing, consider isolating the Turnkey Deals vs. ones with significant deferred maintenance and possibly those that need "lipstick."