Truthfully, while traveling the thing we do the least is rent cars. A lot of the time we just take whatever public transit we can. 

Driving while in foreign lands is often unnecessary and so we avoid it. Between the taxis, public transit or the fact that a lot of the sights in older cities tend to be within walking distance, most often, renting a car just doesn't fall within the realm of necessity. 

But, when we have right circumstances, renting a car becomes a requirement and often little bit of a chore.  

The main difficulty with car rental is finding the best price you can. Many times, you have deals and memberships that you have to balance. Overall, it's not my favorite thing to do.  

A major plus of renting a car over booking hotels and other events however, is that you generally only lock in the price when you make a reservation and pay when you arrive. This way you can shop around without any requirement of purchase or loss of deposit.

But generally, renting a car is avoided if we can.