I'm not sure what kinds of hardware you guys have seen or been marketed. But from my pov, these are all pretty standard features of most hybrid inverters and come out of the box. The only extra expense to not be grid tied is needing a battery and maybe a tiny amount of extra electrical wiring. It wasn't even a question that popped up during my build.

Then again, we regularly have huge rolling blackouts here so we need the inverter to be a giant UPS for the house and be able to use solar and grid at the same time.