I think the best approach would be to get a HELOC on your primary residence. You can then buy investment properties with cash and then cash out refi those to pay back your HELOC. Just limit yourself to only buy what you can with your HELOC and keep paying it back as you refi the investment properties. You will save on interest when you are looking for deals. You can even manage your leverage on your investment properties by not borrowing as much as lenders will lend, but just enough to pay back your LOC. Maybe take out some extra now and then to fund something fun, but you can manage your risk by managing your leverage. This is the BRRRR strategy. You can use your equity through the HELOC over and over again if you manage how you use it!
In our state, I would only finance the investment properties through an LLC with a portfolio lender (small local bank/credit union) using commercial loans. It might sound confusing, but renting a house is a commercial use, even though it's a residential property. These are 20-year amortized loans that have slightly higher interest rates than 30-year Freddie and Fannie loans. If you use those 30-year loans, you run into the 4 and 10 loan limits. The rates are only set for 3-5 years too on commercial loans. That's how they manage long term interest rate risk. There are no limits to how many commercial loans you can get with your LLC! Except the limits set by how much your lender(s) thinks you can borrow and service the debt! ;-)
