I couldn't find this answer either by Google, the archives here or the CO website.

I am on an IAH to LAX trip this weekend and need to check my roller board suitcase, a special metal equipment case and would like to check my small collapsible luggage cart for the metal case as it would save me the ripoff of paying for the airport luggage carts as well as aid in getting to and from my off site rental car lot.

I am Silver Elite (sadly) this year and neither bag exceeds weight or size limitations so the 2 bags will not have a fee. There was a time when checking a small luggage cart like this was no issue but I have not had to do it for a few years. Unfortunately I am taking 2 carry-on items so that is not an option for the cart.

Thanks