1. For a business trip purpose you need to locate where you will stay, when and for how long. Even in a short period of time, you can find beautiful places and serene in almost every regions of Thailand.
2. Are you traveling alone or accompanied by someone else?
3. Which type of tour guides you are looking for? I would recommned you to search on websites or download Apps for finding some of them that near you even local tour guides. (You know that plenty of them are waiting for you to call them for a service)
Though it's rainny season here but we alway welcome you to Thailand!