You could just ask the hotel chains. Although the incremental value of the points is probably small compared to simply making the best deal you can with the hotels.

Again, for the credit cards, just call the CC company. Keep in mind that your employees are probably getting rewards on their cards now, so they may grumble a little if you take those away.

Check with your accountant also if you plan to use the points for personal reasons. The IRS has pretty much ruled that the incremental value of points gained by employees is too small to bother with calling it income (that's not a technically correct explanation, but close enough for now) but if you own the business and are taking the points others get, it's a different story. I have worked for a few small businesses that got rewards on the company credit cards, and they invariably used them for business reasons, like last-minute plane tickets; one used them for a 50" TV for one of the conference rooms.