The best way to address this is to be straight forward. If you have not given him any indication that you are interested in him romantically, then keep it civil and professional.
It is not unusual for foreigners to at times have ulterior motives for connecting with an American- citizenship is one major issue.
Insist that he completes the work (give him a time frame and let him know that you would have to hire another worker if he is not able to finish it)
You should not have to inconvenience yourself. You hired a worker to do work on your home and that is what you;re paying for. Try not to share a whole lot of personal info with him or personal time.