Advise needed for impatiens -busy lizys- flowers?

I have 3 diff types of impatiens (or busy lizys) which i bought this year n doing very well. 1. Short stems beautiful red flowers. 2-tall stems with double pink petals 3- short with nice pointd large leaves n nice dark pink petals. i have planted them all into planters in my yard as i have no garden along wi all my perianels which i startd last year. They all look really nice n i want to keep increasing the plants with cuttings n letting them multiply on their own. I know that all my plants are perenials like lavender, roses, carnations, azaleas, shrubs, etc but i was also told that impatiens are perenials and that they last for years. Now i just been told they are annuals, or bi-annuals. They look so nice that i thought they be stil here for years to come. If they are annuals. Is there any way of preserving them for next year? If i take cuttings then i suppose they wont survive over winter or can i bring them indoors over cold weather? I love to have them for next summers without buying anymore. Can anyone advise me? Also would they produce seeds and how and when and what would i do? I never planted from seeds before. I much prefer to buy young plants or take own cuttings or divide by the roots.