What are the requirements for extending a stay in Thailand when staying at a girlfriend's home?

The discussion revolves around the necessity of filing a TM30 form for foreigners staying with local Thai residents, specifically in the context of extending a visa. It is confirmed that if the girlfriend owns the property, she must register the TM30, ideally within 24 hours of the foreigner's arrival. Additional questions include the timing for applying for a 30-day extension, which can vary by immigration office, but many allow applications 30 days in advance. Key points also indicate that staying at hotels may automatically register the TM30, while staying with locals requires registration to inform immigration of the residence.