My experience with AVIS over the years has been extremely negative, if you have no choice and must rent a car from AVIS make sure you read absolutely every single word of the contract you are given to sign, have complete understanding of all the statements and the consequences, and do not fall for any lip service they give you.

Specific problems I had follow.

Problem #1: I booked vehicle pickup in Germany, the voucher clearly stated that I would take the car out of Germany, the voucher listed each country specifically, and I paid premium for that.
AVIS in Germany presented me with a contract in German that stated (what I discovered later) that vehicle could not be taken out of Germany!
Guess what happens when you are stopped out of Germany?
Guess who is legally responsible for car theft or any damage that may occur, regardless of any insurance you may have?

Problem #2: AVIS staff gave me vehicle without complete documentation, no ownership.
Guess what happens when you are stopped by police or border patrol?

Problem #3: At the time of booking I clearly indicated that payment would be made with credit card covering insurance and I declined CDW/LDW, I made payment in full.
The voucher clearly stated the facts, with balance owing being $0.
AVIS staff presented me with contract in German, I asked questions about suspicious checkmarks on the contract, they assured me that they understood I declined insurance and they assured me that there would be no additional charges.
On my return from the trip I found enormous additional charges from AVIS, when I complained AVIS answer was that I signed contract accepting additional charges!

In the end what may have looked as a decent cost of renting will mushroom into colossal charges that will in some cases be double the price you get from other companies.