Building your REI company's credit

I imagine that business’ have a ‘credit score’ of sorts. If down the road, I want to seem like a good risk, allowing me to get higher LTV mortgages on my investments/rehabs, and better interest rates, etc, what are the best steps?

It seems to me that, like, 99% of this would be about my home buying/selling track record. That probably goes without saying. But, are there better ways than others to accomplish this? Like always use the same bank? Would getting a credit card for my business right off the bat help if I use it, since it would establish my business’ “credit score” right off the bat?

Everything you mentioned will help but most lenders are looking not necessarily for established CREDIT but for an entity that has been established for at least 2 years.

The four "C"s

Collateral. The value of the real estate that you are using to secure your mortgage.

Credit. The way you have paid people in the past is considered a good indication of your willingness to pay money back in the future.

Capacity. Do you have the income to pay this loan and still eat!

Commitment. How much of a cash down payment did you put down?
The amount of cash that you have at risk is an acid test. Why should a lender put THEIR money at risk if you don’t or won’t put YOUR money at risk?