My USA friend is over 50yo. Rather than getting an O-A visa he would prefer to enter Thailand with an O, deposit the 800,000 baht, and apply for an extension during the final 30 days.

Will Los Angeles issue an O for this purpose?

The will not issue a non-o visa for being 50 or over. They will only issue the OA visa.

He should be able to get one at one of the honorary consulates listed here: http://thaiembdc.org/royal-thai-honorary-consulates-general-in-the-u-s/

Thx, ubonjoe.

Follow-up question: person has a multiple O-A issued in October 2016. Enters in November 2016, leaves in February 2017. Re-enters in May 2017, gets another full year. He exits in August 2017, plans to come back in November 2017.

Because his visa will have expired the month before, he needs a Re-Entry Permit to keep alive his last Permission To Stay (May 2018).

Will Immigration issue him a Re-Entry Permit in August 2017 even though his O-A has not yet expired?

Follow-up question: person has a multiple O-A issued in October 2016. Enters in November 2016, leaves in February 2017. Re-enters in May 2017, gets another full year. He exits in August 2017, plans to come back in November 2017.

Because his visa will have expired the month before, he needs a Re-Entry Permit to keep alive his last Permission To Stay (May 2018).

Will Immigration issue him a Re-Entry Permit in August 2017 even though his O-A has not yet expired?

They will do the re-entry permit prior to visas expiration date.

He could gain about 3 months by doing a border hop for a new on year entry shortly before leaving in August. Then get the re-entry permit for that entry.