One of the issues that anyone wearing a lot of vintage is going to run into is the extra care a vintage garment requires. Vintage garments, on the whole, are very well made, and some of them are just as sturdy and durable as anything purchased new today. However, loose buttons and popped seams are often part of the deal when you purchase a vintage piece.
Sewing is one of those essential life skills that I honestly don't know how anyone, man or woman, gets by without. It's just such an easy thing to learn, and it's so handy. Even before I started wearing vintage, I found it helpful to know how to sew a button back on, or repair a split seam. Now, reinforcing buttons and seams is as regular a part of my wardrobe maintenance as washing my clothes.

This dress, for example, is actually in beautiful shape. However, it's also about 60 years old, and the first time I wore it, 5 of the buttons popped off, one right after the other. I wasn't doing acrobatics or anything - one of them literally popped off just from me breathing. After I sewed all of the buttons that had fallen off back on, I went in and reinforced all of the other buttons, loose or not.

Similarly, this coat (which was an absolute steal at only $60) was in perfect condition when I purchased it back in December. However, it's gotten a lot of wear over the winter, and there have been a few issues that needed fixing. I basted together the seams at the buttonholes, which had split, and reinforced the buttons when they started threatening to fall off.
I consider myself a mediocre seamstress at best. I don't have a sewing machine, and I know precisely two stitches. And really, that's all I need to know for basic mending. If you're interested in vintage clothing, but are worried about things like repairs, I would definitely recommend picking up a needle and thread and giving it a go. After all, even if you mess up, all you have to do is pick it out and try again.