All its going to take is one or two very bad, very public deals and then there will be a lot of regulators looking at it very, very hard. 

Best to consult your CPA for the most relevant advice based on your state's regulations and tax implications.

When something is optional, the IRS code or regulations specify a method of electing out.

This will vary based on the owners specific situation and tax regulations in your area.

If the paint does test positive, you'll need to follow regulated procedures to clean it up (or contract it out).  

In the end, we’ll all benefit from personal experiences and how LA county interprets SB9 regulations so we can all better prepare and plan for our projects in the foreseeable future.

The courses you see hawked online worked 5 years ago almost anywhere but that has changed due to saturation and regulations that are now in place or coming soon. 

Quote from @Bruce Woodruff: It's not just about saving money IMHO...it's also about getting out from under their (Air and VRBO) control, regulations, cumbersome and guest friendly customer service et al... 

It keeps things simple and aligns with the local laws and regulations that directly impact your property.

Their content is much less dry, they do a better job of explaining the purpose behind rules and regulations, which I think is very important.