I stay at my GF house when I arrive . Register TM30 online . Done it a few times . Her house details are already in the system now so I just log in and renew when I arrive in Thailand.
I went to Pathum Thani immigration last week as staying near Rangsit. Took Passport copy bio page and entry stamp page . Downloaded TM7 and filled in printed and signed. Passport photo attached to TM7 . Copy of TM30 downloaded from registration website . Also took copy of GF blue book and ID as backup and 1900 baht . Walked in to immigration. Presented documents to reception and was asked to sign 3 other forms given by the reception. Handed in Passport, all documents and 1900 baht. Waited outside for abut 20 minutes. Then called in to collect passport with extension for 30 days already stamped in .
Very easy seamless operation.
Apparently can now upload documents and make payment online and make appointment to present passport and receive extension stamp .
also need proof of address in UK or invitation letter if you are staying with friends or family.
I applied from Malaysia as we were resident there earlier this year. She got 1 year multi entry with 6 months max stay . We went back in May . No issues at all .