Don’t know much about the event venue world, but my initial question (which sounds like you’re thinking of) is how frequently would this realistically be rented out for events? Need to understand the local market and demand.
Further to that, why would some pick you over any other event space besides being on the river? Does it fit the vibe for the events you’re talking about (eg wedding where people may be looking for something with good ambience and intimate feeling than corporate space feeling)? Is waterfront as big of an appeal / attraction as you think (not saying it isn’t bc I like the thought of looking out over a river, but not just for the sake of looking over water if the rest of the surroundings and vibe aren’t great).
In terms of your other comment, how do you know the prior business failed due to lack of marketing and not simply lack of demand for the space? I get the play on the development of a low income area, but that can be a very long term play and very well not play out as you think it could.
Is the place easily accessible for the type of clientele you’d want? Depending on the area and what people are accustomed to, they may not want to trek very far when there’s another good enough venue closer.
If you’re skilled enough in it develop a case study / test and make them do it. Anyone unwilling to prove those basics skills they purport on their resume aren’t worth hiring IMO. And kind of a separate ballgame but most major consulting firms have these kinds of case studies as part of the interview process where those technical skillsets are required.