Can I ask for a raise when I realize I'm underpaid after a job search because most other companies are paying more for the work I'm doing?

You can't use any of the information you've collected in your job search to make the point that you believe you're underpaid. A much better approach is to compile a list of your own achievements over the last several months - goals met, objectives achieved, initiatives taken, extra responsibilities assumed - anything that will show that you're not only doing a great job, but more than the job requires.  Ask the president for a performance and construction salary review, take two copies of your list, one for you and one for the president, so you're both looking at the same information, and make that point that  in light of what you've accomplished you feel a construction salary adjustment is in order A much better approach is to compile a list of your own achievements over the last several months - goals met, objectives achieved, initiatives taken, extra responsibilities assumed - anything that will show that you're not only doing a great job, but more than the job requires.  Ask the president for a performance and construction salary review, take two copies of your list, one for you and one for the president, so you're both looking at the same information, and make that point that  in light of what you've accomplished you feel a construction salary adjustment is in order.