@Michael Neiman First of all, congrats on jumping in! I too started an LLC with a buddy about 6 months ago and we just locked in our 4th house. My advice: buy a house. You won't be able to stop at one.
The challenge you are describing is one that we faced as well. With 5 of you, your best option will be to secure a loan through the LLC.
We called around until we found a local bank who would do 80% ARV loans. Most lenders said 80% ARV or 80% loan-to-cost, whichever is lower. That is not ideal if you're looking to BRRRR as it means that no matter how good of a deal you find, you're always going to need to put 20% down.
Here is how it works with our lender. We get a property under contract, get an inspection, draft up a repair list with associated costs and submit to lender, he then gives that list to the appraiser. The appraiser then takes that list and appraises the house based on what it would be worth once those repairs are made. That number is our ARV and the lender will give us a loan to our LLC for 80% of that number. So, the formula for us when we look for properties is simple: purchase price + rehab must equal 80% or less than ARV. Another rule of thumb of ours is that the property must rent for over 1% (ideally 1.5%) of ARV or else we're underwater.
Current terms are 6% interest, 20 year am, 5 year balloon. Additionally, the loan is interest only for the first 6 months. We are going to revisit these terms for future properties b/c margins are slim on anything under 1.5% purchase price to rent. However, it's really nice to be able to buy several properties with little money.
My advice would be to search the BP forums for others doing BRRRR's in your area. Send them all private messages asking for a BRRRR friendly lender they recommend. That's how we found ours. Wish you the best! Let me know if you have any questions.