The mooring field at Stuart is managed by the Sunset Bay Marina, and the cost depends on the size of the vessel.
Regarding
anchoring in the area, the most common area where transients anchor is in the southern branch of the St. Lucie River, across the channel and slightly south of the Mooring field. Technically this area is not within the boundaries of the city of Stuart and is part of unincorporated Martin County.
Vessels also anchor in the northern branch of the St. Lucie, typically across the channel to the north of G5. This area is further from Sunset Bay however.
In the same area, vessels anchor in Manatee pocket, closer to the
ICW and St. Lucie inlet, however sometimes it can be tight in there.....
From time to time there are vessels anchored in Hooker Cove on the St. Lucie near Manatee pocket. However, this area is fairly far from everything/anything and is mostly used for staging to make a trip
offshore.
There is (was?) an online site that detailed the city of Stuart’s “anchoring regulations”, but from what I have seen in the last several years, no one pays much attention to it.