You should ensure you have the appropriate medical insurance. Check with your carrier to determine if you are covered in Canada. If you are not? Then yes, get some. Your vehicle insurance is good in Canada. Some folks get a card from their carrier that states your vehicle coverage.
It appears that your knowledge of border crossing may be somewhat limited. Ask questions here...
A for instance...if you have handguns...don't be bringing those. You need a passport to re-enter the US. If anyone in your party has a criminal record, they are inadmissible. Lots of the laws, at first glance, seem kind of harsh...you will find the laws are the same/same...going both ways. The absolute best way to cross the border is to have an empty fridge. The rules change often..so..no veggies or fruits. Onions or garlic? no no no...Pet food if it is made in the US in it's original container.
Gary Haupt