HELOC affects on DTI - question!

[Hanan K.]

Hello BP members! We are preparing to leave our W2 jobs in a few months to move into full time real estate investing. 

We have a good amount of equity in our primary residence as well as one of our rentals and we would like to take out a HELOC on each property but we plan on purchasing a few investment properties before leaving our W2.

1) Should we apply for the HELOCs First? Will this affect our DTI even if they are at zero balances?

2) Does it make more sense to buy the rental properties first?

3) Is it possible to apply for multiple HELOCs on different properties at the same time? or do we need to do one at a time?

Thanks in advance!