Just a little sideline: Getting services from the towing/salvage co's is somewhat negotiable, depending on circumstances. A few times while owning this small marina I have been involved where a recovery could be construed as a salvage. In all cases I advised my tenant to discuss what the billing would be like prior to accepting the service. In each case they came to terms and the tow co stuck to the agreed terms.
This would be impractical in a situation with true peril, but seems to work well when no crisis is involved.
In one case, a tenant 27' sailboat ended up in the surf (mild surf) on an NC beach and I heard him call on the VHF. I run out there in a skiff and both Towboat and BoatUS arrived at the same time, having heard the same VHF call. Owner was frazzled (no kidding there) and I asked him if he wanted me to handle it, to which he agreed. I got the two into a mini bidding war and got the fee down to I think $1300. Winner pulled the boat off, got paid what was bid, and all went on their way. No claim for salvage was made.
The point is, discuss the terms before engaging their services. And have a witness listen in if possible.