Where did you apply from? I think the embassy cost varies slightly too , it says 18,000 on their website so maybe you got lucky before they put it up, still well worth it in my eyes to get peace of mind and quality standards are there
Issa compass charge 18,000 baht so 600usd , they use AI software also to check & this includes the cost for the visa fee for DTV so works out about $120 for their fee