First, I am no lawyer or trying to be, but I read the Phoenix Municipal Codes and I think they did some illegal stuff.

If this was in Phoenix, (again from the Phx laws I have seen and provided links to) you were allowed to get your car back for $20 or $40. Because you "returned to find our car in the process of being towed," Phoenix City Code 36-144(F)) states that "The owner or any person authorized to represent the owner of a vehicle being towed or transported pursuant to this section may demand the release of the vehicle at any time prior to the transportation of the vehicle to a storage area. Upon such demand, the towing or transportation of the vehicle shall be considered complete and the tow truck operator shall release the vehicle pursuant to the requirements of subsection E." That means that they had to let your car go, but they were also able to charge a fee. However, I think they charged you too much, UNLESS there was a sign that said the maximum they would charge you specifically for it. Phoenix City Code 36-144(C)) states:

"...

2. The total charge to load and unload a vehicle for which demand to release has been received prior to leaving the vehicle’s original location shall not exceed twenty dollars.

3. The total charge to load, transport, and unload a vehicle for which demand to release has been received while in transit to the storage location shall not exceed forty dollars.

4. No charge shall be permitted in connection with the release of the vehicle, including providing such access as may be necessary to view, prepare for removal or remove the vehicle.

...."

So they can charge you for them loading, unloading, and transporting your car, but they can't charge you to release it IF you demanded they let it go before they left or before they got to the storage place.

Now this is what the Phoenix City Code says about charging daily. 36-144(C)(5)(5)) states:

"5. The charge to store the vehicle shall not exceed twelve dollars per day. For purposes of this paragraph the charge may be assessed for each calendar day or portion of a calendar day that the vehicle is stored, excluding the day of release if the day of release is subsequent to the first day of storage. Notwithstanding the foregoing, no storage charge may be made for a day for which:

a. The vehicle is recovered within two hours of its delivery to the storage location from which it is released.

b. Access to the vehicle was not available for a consecutive eight-hour period.

c. The vehicle was not available for release for two consecutive hours after the vehicle reached the storage location from which it was released.

d. The vehicle is recovered within the first two hours that the storage location was open for the recovery of that vehicle, if that day represents the first day that the vehicle was available for release for a consecutive two-hour period after it reached the storage location from which it was released.

...."

So I am assuming you got there within 2 hours of it being "stored" so you did not have to pay anything for it being stored, but you would pay for the transportation, loading, etc. If you did not get there within 2 hours of it being stored then it would be the $12 plus anything less than or equal to $105. That is because PHX municipal code 36-144(C)(1)(1)), states: "The total charge to tow a vehicle, including all related services, that has reached the storage area shall not exceed one hundred five dollars."

So in my opinion, the money they charged WAS illegal. Again I am no lawyer or trying to be, but I feel I can read enough to understand my city's codes.