There are some products you just shouldn't say no too! These products you definitely want in your makeup kit. Lip tar by Obsessive Compulsive Cosmetics is one for sure. At $12.50 each they come in a tube and are available in a variety of colors. I've used them on plenty of shoots and definitely recommend them. A little also goes along way with this product, not too much is needed and it feels like you're wearing nothing on your lips! I do recommend to use a brush even if you are not a makeup artist, it can get a bit messy just using the tube on it's own. Camera ready cosmetics has stainless steal palettes you can use for mixing any kind of product and apply with a brush from there.
Another product is the Makeup Forever flash palette! A bit pricey at $95.00 on Sephora or directly from them in their NYC store. A very highly recommended product for two reasons, you need bright bold colors for photo work and two you can do just about anything with this palette. You can use it for lips, eyes, and face. Only certain colors can be used on the eyes and certain colors on the lips, it all says which ones not to use where on the palette.
And for a last product, basically anything by Yaby Cosmetics. I love their free style palettes! You can customize with any blush, lip gloss/stick, eye shadow, and foundation. All of their products are at reasonable prices and are amazing on camera! Each eye shadow is about $2.99, blush refills at $11.99, and lip refills at $3.99 just to name a few prices. I also love having palettes, definitely easier to carry in my kit. They also have whole ready to go palettes and liquid foundation which is amazing. For $12.99 a tube, the coverage is great and a little goes along way so you don't feel like you're wasting anything and will last.
Here are some links:
http://www.occmakeup.com/liptar.html
http://www.sephora.com/browse/product.jhtml?id=P219411
http://www.camerareadycosmetics.com/products.php?cat=55
