Most people don’t care about being CO2 neutral. The real question is what is the ROI? Will the panel save that person money. If it takes 50 years to pay for itself, I’d say that’s bad. 10 years is more standard. 5 years I say it’s a no brainer. Though I suppose you can also argue value for utility, if that is giving her the ability to power something off grid that would be worth something.
In Germany those panels usually pay themselves after about 5 years depending on the price of the necessary electronics (don’t forget the electricity meter!) and if there’s also a battery.
You don’t need a smart meter for this, just plug and play. If seen offers for complete sets from as low as 250€ in supermarkets, so almost everyone can get one and start saving some power.
