How often does a property owner need to report a TM30 for a long-term tenant in Thailand?

After each return from abroad!

No.3 is correct already confirmed with Nonthaburi Immigration officer

Last renewal I had (Phuket in April) they gave me a lot of grief over my TM30. I had not gone abroad or even an overnight stay away in a hotel.

As a result, I had to return and get all new documents including a newly completed TM30 form.

I am aware that, at the time, they were targeting to ensure people were staying where they said they were, but I had been in the house 4 years and never had issues previously.

It was very frustrating but I was able to obtain all documentation from my landlords and complete my renewal on the same day.

You need to contact your local immigration office and ask what their policy is. There are 3 different policies that various immigration offices use.

1) most offices require you to have a new TM30 every time you leave Thailand and return, but you don't need a new one if you traveled around inside of Thailand and return to your address.

2) some offices require you to have a new TM30 any time you sleep 1 night away from your home and return.

3) some offices don't require you to file a new TM30 as long as you're returning to the same address, even if you leave the country.