I am flying UA to BKK with a 2 week layover in NRT. When I arrive in BKK, I plan on staying there for a few days then continuing to Phuket (HKT). The flights I am seeing right now are for AirAsia and ThaiAirways costing $80 and $350, respectively. If I can save myself $270 I don't care much about picking up the extra miles for a short flight. But the issue is the baggage policy on the AirAsia flight. I have one bag for business and the other for vacation. I really don't need to carry my work bag around when in Thailand. I was wondering what the policies are regarding lockers in the airports? I will consider suggestions outside of airport lockers if anyone has any. Also does anyone know why ThaiAir is so much more money?

Thanks.