I got solar recently because the payback time was around 5 years taking rebates into account. We often talk about how negative externalities of things like coal are not priced appropriately, however it goes the other way and renewable rebates exist due to the positive benefits.
I wonder if in the situation you mentioned, whether it would be profitable for a third party to handle the roofing and capture any value while covering the costs. The ROI might be a little too low for a traditional business but it seems fairly low risk and effort and would scale nicely if they get installation discounts. It would still be a lot of friction starting a business if you have to wait for them to do it, so many laws like this often only activate for businesses over a certain size (such as GST in Australia based on revenue, or WorkChoices based on head count).
I wonder if in the situation you mentioned, whether it would be profitable for a third party to handle the roofing and capture any value while covering the costs. The ROI might be a little too low for a traditional business but it seems fairly low risk and effort and would scale nicely if they get installation discounts. It would still be a lot of friction starting a business if you have to wait for them to do it, so many laws like this often only activate for businesses over a certain size (such as GST in Australia based on revenue, or WorkChoices based on head count).