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At these spending levels you will need substantial credit limits, and will likely end up using business cards, rather than personal cards, unless your personal income alone will support them. Business cards require a personal guarantee and are based on your personal creditworthiness, but the issuer will also take into account the company's cash flow.

American Express issues charge cards with no preset spending limit (Green, Gold, Platinum and Centurion), and also credit cards (including the Starwood card) which do have specified limits.

Chase Ink Bold is also a charge card, all other Chase cards are credit cards. Some Chase affinity cards have business versions (e.g. United Airlines), while others do not (e.g. British Airways).

Business cards offer useful features in a business context, each physical card has a separate account number which makes it straightforward to track spending, set individual limits, and replace individual cards if lost.