Bigger Pockets Ultimate Starter Guide, 2 noobie questions

[James Freeman]

1. The guide says shoot for 2% of purchase price for rents, assuming that wont fly in Austin ? Also says for flips use the 70% rule and ive been presented a few deals now that are not close to the 70% ARV after purchase price and repair estimates. Are these both still valid ?

2. Is it a viable way to start by buying a new primary residence and renting out my current house ? house hacking may not work for us due to need for at least 4 bedrooms.