Mossberg 500, 590, or Remington 870 are the most common answers to this question.
Then you get into the semi autos.
Really need to know what your budget is.
posted from my stupid smart phone, please excuse any spelling mistakes.
"If your plan is for one year, plant rice.
If your plan is for ten years, plant trees.
If your plan is for one hundred years,
educate children." -- Confucius