What are my options for extending my stay in Thailand beyond my current visa until January 14?

Thanks in advance for your advice everyone!

So I’m not looking to stay in Thailand long term, at least not yet - I’m just figuring out my extension option so I can stay until my lease ends Jan 14 and complete 3 months here.

My current 60 day visa on arrival ends Dec 6. I could do the 30 day extension for 1,900 baht until Jan 6 but that leaves me with 8 days and I’d like to have a bit more flexibility to stay until the end of my lease.

So it seems I’m left with either the border run to Laos option which appears to cost roughly 6,300 - OR I could also fly roundtrip to visit friends in Malaysia for 5,500. But that also assumes that doing the border run or flight to Malaysia would actually give me a new 60 days and not just 30 which isn’t enough.

Is there another simple option here?

Will I definitely 100% get another 60 days and not 30 days by going to Malaysia or Laos?