Welcome Farrah, most mantids are cheap, like as stated above, the sp. are the ones that attract most new comers...
The good news is, if you decide to breed them, you don't have to wait long like panthers lol.. Parsons are another story when incubating lollolol
Mantids lives are short, but their offspring will brighten your day. And if you do not want to breed them because you do not want to care for their young, you should totally sell or better yet just let somebody pay for shipping and borrow a male... It's a bad thing to let an adult mantid not be used for future generations.
An awesome mantis that isn't hard to get to adult stages are Ghosts and Gambians.
I have a little male Acontista Multi color if you want to start out small lol, he is tiny! He is cute, is a two week old adult, so you might only have another month or two with him before dying from age, but he only requires 7-8 fruit flies a day and one misting every other day. He can also be kept in a 32 ounce deli cup with a few fake leaves in it for him to get water and climb around on.
If you let him out, make sure you are in an open room with very little places for him to escape and hide in... He'll fly! You can check out his beautiful colors! His wings are a bright Violet with some deep purples!
Just pay $7.00 for shipping and you can have him, that is, if you have a cup and fruit flies on hand.