To add more confusion on the subject of the TM30, according to the law firm konradlegal.com, the hotel or rental place must submit the TM30 and as long as your TM30 shows you're within your allowance (mine is 365 days), you don't need to resubmit a TM30:
TM 30 Registration for Short Time Stays
You might be asking if you need to record your residency every time you go away for a few days and come back. This is dependent on whether you return within the stay term set on the most recent TM30 you submitted.
You do not need to submit a new TM30 if you return within the time frame stated on the form. You must submit a new form if you return beyond the time frame specified on the TM30.
If, for example, your most recent TM30 indicates that you will be staying in your home property for another three months, you will not need to report when you return home.
If you live in a rented residence, the same regulation applies to your landlord.
In this case, your friend, like a hotel, still he/she must disclose your stay. This is because your most recent place of residence needs registration in the immigration database. This database is under Section 37 (2) of the Thailand Immigration Act of 1979.
It’s a different matter if people truly follow this guideline, and let’s face it, most people don’t.
Remember that if you stay in a hotel or guest home, you won’t have to bother about reporting because they will take care of it for you.