@Ari Steinman - if you are asking lenders for interest rates be sure to ask interest and discount points, because interest rate is 1/2 of the equation. If I can get a 6% 30 yr fixed on a rental, that sounds great, until I tell you its $30,000 in discount points to buy the rate. Rate + discount points!
Any conventional loan in America is not allowed to close in a LLC. You must either close in your name or in the name of your trust. But, you can move title to your LLC immediately after closing. Fannie Mae is fine with this as long as you are the majority member of the LLC.
What downpayment are you looking at? If you want the best deal, rental properties with 25%-30% down are getting better financing terms than 15%-20% options.
Only DSCR loans will have PPP (prepayment penalties) and they range from 0-5 years depending on the lender and what you want. You can take a higher interest rate and select a 1 yr PPP for example. Or, maybe you want a lower rate and you are ok with a 3-4 yr PPP (which is too long IMO).
I am not sure what you mean by "supplement" to the loan after you raise rents. Can you explain?