Thanks for your question.
There is obviously no central registry of art galleries which you can check against in the same way there is for charities for example.
There website is reasonably professional:-
It suggests that the gallery was formed in 2007. It's not clear what type of business entity it is. It does not mention that it is a limited company and there is no company registered at Companies House under the name of "Lloyd Gill Art Gallery" (or anything similar), but usually galleries are run as partnerships in any event and, again, there is no central registry of partnerships for you to check against. You should enquire of this, they will likely confirm it is run as a partnership/sole-trader
I would suggest calling round local art dealers to see if you can get a handle on their reputation. If the terms are uncompetitive then there is nothing stopping you re-negotiating the terms after enquiring as to why they adopt this unusual practice.
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