For your reference as following:
1．” who only work in houses not in restaurant” for my understanding, do you mean those selling food in their own houses or rented houses without a business license? If yes, for those waiters working in such condition, may be you can call them “服务员”, or just to say “在里面工作的人员”.
2.” I buy airplane ticket from online shopping.”我在网上买的飞机票 or “我上网买的飞机票”.
3. The opposite of 故意in Chinese is 无意 or 无心 or 意外.
Hope could be helpful :)