Just a quick mention of this drink holder. Holds 2 drinks, can clamp on to virtually anything. Works great for clamping on to a cart pole. Made well and very durable.
https://www.amazon.com/ROBOCUP-Colors-Fishing-Wheelchair-Microphone/dp/B0065MYZGW/
https://www.amazon.com/ROBOCUP-Colors-Fishing-Wheelchair-Microphone/dp/B0065MYZGW/