What is the least expensive way to rent a car, in terms of the rental company, online special rates, etc.?

I used to work for Alamo Car Rental, but that was 20 years ago and I have not rented a car since then. I just checked their weekly rate for an Economy car and they are not as low as I had hoped. They used to be one of the lowest priced of the major rental companies. But that's no surprise, I always thought that the car rental industry was one of the shadiest businesses I have ever worked in, trying to frighten renters into buying optional insurance coverages they usually do not need if they have their own auto insurance. Management made no secret that rental companies made little or no profit on the actual rental fee, the majority of the profit was made on the insurance coverages. Now there is a long list of extra surcharges and taxes that I don't think even existed in the industry 20 years ago. Would I save much money renting a car through Priceline, or other online specials? I welcome all answers/suggestions.