agree, focus on brushes, because good quality brushes are the key to makeup application, and can last for a long time, with proper care. the pret-a-porte brush collection is a good idea, if you can get it. also pick up mac's brush cleaner, as i feel it's the best to prolong the life of your brushes.
here's what i would consider "basics":
brushes: the 187 would cover both liquid foundation application, as well as taking care of many powder and cream face products. because its more versatile, that's why i choose the 187 over the 190 foundation brush. if you want a seperate foundation brush, the 168 angled brush is great for application and contouring. the 150 powder is good, but not essential. sugar cosmetics makes a great powder/buffer brush, it's pink, and it's only $16. for eyes, the 239 for packing on color, the 217 for blending, the 266 for liner and brows. the stila #4 is the best all-around for lining and detail. the 316 covered lip brush is nice, but not essential. the pret-a-porter is worth it, because they're full-size brushes. don't waste your time with the brush sets, they are nowhere near the quality. instead, focus on building a full-size brush kit, little by little. you really can't beat the quality of the full-size mac brushes.
face: a good foundation is key, i like studio fix fluid myself. a couple blush shades, say a shimmery tone that is still close to your natural cheek color, and then a slightly darker matte shade, for contouring. a good loose or pressed powder to set makeup, and blot shine, i like loose blot powder. also, i'd recommend a good concealer. if you want, you can branch out and get a good cheek highlight, such as a mineralize skinfinish (limited product only released a few times a year) when they come out the day after x-mas. i would also recommend a primer, such as prep and prime skin.
eyes: a good base, to begin with, such as urban decay primer potion. as far as eyeshadows go, i'd recommend getting a 15-pan, or a few 4-pans, and then asking a makeup artist to choose some colors for your skin tone and features. i would say, a good neutral highlight (such as phloof or shroom), a good color for filling in brows, and a good black, for smoky (carbon). beyond that, it's all about person preferance, and what colors you wear the most. if you can get the shadows in pan form, you'll save some money. blacktrack fluidline is my staple liner. beyond that, if you wear colored liner, get a couple of colors of fluidline, or kohl pencil. if you want some colored bases for your shadow, a few paints or shadesticks. i don't like mac mascara. i'd recommend looking for mascara elsewhere, to be honest. diorshow is good, as is benefit bad gal lash.
lips: again, this is mostly preference. a good primer, again, is a great idea. prep and prime lip works well. a good neutral lip liner close to your natural lip shade i use mac lip pencil in whirl. if you tend to wear a lot of a certain color on your lips, get a lip liner close to that color. a few lipsticks is a good idea, a few lipglosses. mac has a LOT of lip options, so go with what you like. i personally prefer the pro longwears, and the lustreglasses.
skincare: also very, very important. mac microfine refinisher is great, it's a mild dermabrasion scrub, to be used a couple times a week, that really helps slough off dead and dry skin, and smooth out blemishes. also, a good moisturizer. you'd be amazed how good skin can help the appearance and application of makeup. fix+ is another must, it helps keep your makeup looking fresh throughout the day. the spray bottle lasts a long time, and also smells good, lol.
basically, my recommendation is to just go to mac, take your time, play with colors, and don't be hesitant to ask questions. "basics" differ from person to person, because we all have such different features and different tastes. $700 should be MORE than enough to build a fantastic collection, so find what you like, and make a list. also, browse the FOTD section, see what looks you like, and what colors were used, which might give you and idea of what items you might want to take a look at. oh, and i believe mac has a $500 maximum purchase limit, just a warning..
