Certainly, owning a boat is only economic if you succeed in using it more often than the cost of hiring one, from time to time (and accept that hiring comes with the problems of a suitable boat not being available at the time you want to use it).
Tolls, insurance, berthing, and maintenance all have to be factored into the equation.
Owning two boats, probably means that you will only have time left for eating and sleeping - and that's not good for your relationship with wives, husbands, family, employers, customers, etc.
I'd post an advert for the SeaHawk on the "For Sale" section of the forum and seriously consider whether hiring would be a better bet for you than keeping your other boat.