Business credit cards for LLCs vs Tracking rental expenses?

[Cynthia Oistad]

My husband and I own two single family rental properties, one in Alaska, one in Las Vegas. We have a separate LLC set up for each of them and a separate business checking account to collect rents, security deposits and pay SOME expenses. We have been collecting all the rental income into each LLC's respective business accounts and set up "auto-pay" payments like utilities to come from those business checking accounts. We do not yet have a credit card set up for those LLCs. When we have had to purchase supplies/materials for those rental units, we have been using our primary personal credit card to purchase those items (whoo hoo for AIRLINE MILES!) but immediately tracking/recording the business expenses under each LLC in a ledger and filing away the receipts for our annual tax preparation.   

Question 1: Even though we are careful to track ALL rental expenses that are paid using our personal credit cards, is that enough separation from personal accounts or MUST we open a separate credit card for each LLC? I do not like using the checking account to pay for contractors, repairs, materials etc because we don't get any benefits, miles, cash back. But I want to be squeaky clean also if we have to prove that our LLC finances are separate from our personal affairs in instance of litigation. Is the tracking of all business expenses sufficient?

Question 2: We are in the midst of shopping for a third investment property now and hope to make an offer and close in the next 60 days.  I have heard it is not wise to open up new credit cards while in the midst of securing a loan as it can lower our credit score. Normally we would just wait until after closing on the third property to apply for a business credit card but we are about to undertake about $10,000 in renovation expenses on one of the properties in the next two weeks and I would like to use a credit card to pay for our materials and also our contractor (if possible).  Is it ok to keep using our personal card for these types of expenses?