Critical question, especially if you wish to avoid conflict with third parties and possibly land a #trademark infringement lawsuit! Add to that any rebranding costs after 2 or 3 years after starting operations…Ouch!!
The question is typically avoided by clients because there are costs involved. The risk of conflict always exists but the risk must be managed with a well-run trademark search and clearance by your attorney.
Depending on whether the mark is strong or weak, additional comprehensive searches may be required. Usually strong marks do not require additional comprehensive searches as opposed to descriptive or generic marks. Other factors apply, of course, such as channels of trade and distribution, overlapping goods and services, meaning of the marks involved, etc.