It depends on what kind, as there aren't any viable fusion designs yet. If they involve gigantic magnets or largish amounts of material at surface-of-the-sun t

It depends on what kind, as there aren't any viable fusion designs yet. If they involve gigantic magnets or largish amounts of material at surface-of-the-sun temperatures or incredible amounts of neutron flux, costs are going to be high and safety is going to be a problem even compared to fission. If they can miniaturize it like the Lockheed guy in the OP wants then not so much but nobody really knows if that's possible.