30 Day Extension on a METV

[bangkok 2016]

HI Everyone,

This is my first post and my English is not very good so please be gentle with me,also apologies if this has been answered/covered before. My current situation is that  my 1st entry into thailand was on 19/10/17 and expires on 17/12/17 so my questions are as follows:-

1) Can I get a 30 extension on METV Visa at imigration office ?

2) If I can, then which imigration office do I need to go to in Bangkok and what paperwork/documents do I require ?

3) How early can I apply for the extension ?

Thanking Everyone in advance.