Advice needed

I have lived in Cambodia for 3 years all Cambodians are paid between $2.50 and $3 per hour that's for 12 hour shifts 6 days a week the average wage for police and army low ranks is $70 per month I have a girlfriend she works 12 hour shifts 28 days straight with 1 day off each month no paid public holidays even xmas day no overtime rates and her boss sometimes asks her to do over time sometimes 3/4 hours no extra pay she gets paid $100 per month but if she misses 1 day off work because she is sick the boss takes back $10 per day shes off work she is luck with her wage as most do more hours for less pay so $300 per month is good money and why hire some at $300 when they can hire a Cambodian for less than $100 per month

You are correct (for once!) regarding average Cambodian salaries . But $300 for an expat salary seems extremely odd.

OP, do you mind letting us know what your nationality is and the type of job that you have been offered? As this may explain the salary a little more,  the rest of the offer sounds like a good deal though.