A single rose will be beautiful, elegant and simple. I know because this is what I almost did for my wedding... I happened to know the florist for a long time and he upgraded me to 3 roses. Tie a ribbon around the stem to match the dress and it will be PERFECT. I also was on a strict budget for my wedding. Here are some things I did to cut costs.....
1. Guest list of only close friends and family, kept under 65
2. Made my own invitations on the computer
3. Ceremony and Reception in the same location
4. Wedding was on a Sunday afternoon (typically Friday nights or Sunday afternoons are less expensive)
5. Made my own favors (chocolate lolly pops) and tied with personalized ribbons I ordered from EBAY
6. Made my own sign in book.... wasn't a book...I placed a photo of me and my fiance in a mat and had everyone sign that
7. DJ instead of a band (some may say you don't need music/dancing....this is NOT true. The top three things people rememer about a wedding is the bride, the food and the music!
8. Keep centerpieces simple too.... A single rose in a stem glass with some greens and baby's breath.... simple, elegant, and will match your bridesmaids flowers :)
9. Use an easle with a handmade decorated board showing the table assignments instead of individual placecards
10. Alcohol..... see if venue will let you supply your own. Anything unopened (except beer) and unchilled can be returned to the liquor store.