Travel agents are for people who can't figure out how to book a flight or hotel, they essentially look up Skyscanner like you can do and add 30-50% to the price of the flight, then look up Agoda like you can and add 30% to the price of the hotel....book your own flight and hotel, it's really not that hard .....
When people say a contract, do you mean a one page letter explaining your role, duties ect or a legit contract, 20 pages with stuff like what's acceptable in the workplace, annual leave allowances, sick leave ECT....
isn't sending $2.5k to some random Thai visa agency while your on the other side of the world risky? That's easy pickings for them and what are you doing so do, call the police ?