Many people want a lot of gears, if they ride in steep hills, with their folding bike. They often pay much money for an eight or even twelve gear bike.

But IMO it suffices to have just one gear for that, namely a moderately low gear. One can use that also on plain terrain, against strong winds, and with heavy luggage, older age, and little muscle power.

Having just one gear will strongly reduce the weight, size, cost and repair time of your bike. And you can also do steep climbs walking or running along your bike, esp. with heavy luggage. That is also a healthy workout. So you can keep it cheap and simple.

It is also possible to choose an additional extreme low gear to have two gears. Why do you want more gears?