I think you might be thinking of someone elses.... I did my own, along with a magnet, but have not posted them yet. I did 100 of them.
The magnets were 150.00, materials were 50.00, and printing was 115.00. But, these will serve as my std's and invites. I don't think you have to do both... I am having them rsvp to the stds, so what would I send out more invites for. I do plan on send an info packet closer to the date, but then only to the people who are coming.
I think that I would recommend having them done for you- just because they were a hassle to me, and are nothing special...