If you are considering to change your job, make sure you do proper research of your future employer. As a candidate you should insist in being interviewed at their premises and not in a hotel meeting room, or God forbid, in Starbucks.

Do not accept the pressure by the recruit company or their client's HR Manager to sign an employment agreement, without first taking your time to review the agreement. Perhaps seeking advice from a friend. Too many contracts that I see are not fully in compliance with the Thai labour law. 

Making a job change is big, it is indeed like buying a house. Who will do this over the phone and from having seen some details on a web site?