回复：Please help on visa/greencard quetions:

My parents are over 70 and both have retired. They are visiting my sister in Canada now. Their USA visas expired a few months ago and their Canada visas will expire next April. Can they go to the USA Consulate in Canada to renew their visas and fly directly from Canada to USA after their Canadian visas expire?

-Yes.

 Or should they go back to China first and wait a few months to renew their American visas in China and then come to USA?

Also, I am currently an American citizen. I am planning to apply for green cards for my parents. Should I start the process while they are still in Canada or should I hold off the process till they come to USA next April or after?

-If you do that, they will be trouble to enter US using B2 visa due to immigration intent. So, you had better sponsor their green card after they enter US for about 3 months or more later to avoid any trouble.

 Could you please let me know which option is faster?

Thank you very much for your advice