I believe it is still illegal in RI to preclude outside contractors but many yards require a commission on the work making it for all intents and purposes difficult. As to where to store/work on a boat, you have a choice which ranges anywhere from Newport
Shipyard, a myriad of other Newport marinas
, Jamestown marina, a few Brewer yards, Wickford marina, Portsmouth as others have suggested, etc... the list is almost endless... Some may have some limitations but there are many from which to choose.
If you are a yacht club member
, that opens a larger list.