Very, very, finger in the air:-
120W panel - 2k Baht
Simple PWM charge controller - 500 Baht
50Ah deep-cycle battery (lead acid, not really worth going lithium for a tiny system) - 3k Baht
1,500W pure-sine (important for a motor) inverter - 3k Baht.
Add the bits n bobs to tie it all together, you're off and running for 10k ish.