Hi! Just passing by and thot I'd share my experience.
If you're looking at standard card printing and making, it should not cost a lot to get them done. Whatever you managed to save on printing will be a tiny fraction of what you would be spending on bridal package or wedding banquet. So it doesn't make sense to harp on it too much.
I wanted to make my own cards from the start so I did just that. But to save time, each card was an A4 coloured paper folded into three sections. On the inside you'll see Chinese invitation on top, English invitation in the centre, and programme at the bottom. I had a programme becos we did solemnization before the tea reception. If you have no programme, you could insert pictures that you like or want, or even the map.
On the outside, I drew and scanned a picture on the front cover (found on the net) - this is top flap. The second flap that you see once the cover is opened was printed with a theme using wordart. I used A Knotty Affair (as in tie the knot). The back of the card was simply our names and the wedding date. I also made a ribbon to stick on the cover of each card to make it look 3-D (idea from the net again).
It took sometime to get the first copy right - position of the pictures and words etc. But once the alignments are done it's just printing, sticking, folding and writing the guests' names. My friends liked the card. They may not keep it but that didn't matter. I just wanted something personal and it will be kept in my wedding album for keepsake.
I made 200 cards and changed cartrdige once. Cost depends on what you use for the paper, ribbons and other accessories. You can also use lace, beads.
I've learnt that if you wanna make your own card, you must first know what you want to put on it. And you must make them in the easiest/least hassling way to save time (and sanity if you have many cards to make).