What Paints Do I Buy?
So what kind of paints are good for mini painting? The two main types are acrylics and enamels.
Acrylics are water-based paints. Note that when you paint any water-based paint on a miniature, small flakes of paint will come off with use. I can verify this myself, as I was very surprised to find it happening to my own miniatures. Before learning why, I was boggled as to why my paint was flaking off. To prevent this, you can paint a small layer of varnish over the miniature.
Enamel paint will dry with a glossy finish. Other than that, enamels can vary from brand to brand. Previously, enamel paint was always oil-based (while acrylics were water-based). Now, however, enamel water-based paints have been introduced into the market as well, making it even more difficult to identify the correct type of paint to purchase for your needs.
Different people recommend success with different types of paint when painting minis. Personally, I use acrylic paints and thin them when necessary with water. Others have reported success using enamel paint mixed with paint thinner (instead of water). Acrylics are usually a safe starting point, but if you're serious about painting minis, I'd recommend testing both types of paint and seeing which you prefer better.