Your overall budget depends on what you can afford and what you want. I have recently (last couple of months) realized that trying on clothes before I buy is a huge money/time saver, and it is a lot easier than I expected. Rather than grabbing something off the rack and returning it/just keeping it, I try it on. This has also been a help with make-up at the more upscale department stores. It's more expensive for the make-up, but I could have saved a fortune getting the right color the first time. I would suggest looking online to get an estimate of what you like, add a little to it, and go shopping.
A waist cincher will run around $60. The only stores I have found waist cinchers at are adult type stores. There are nasty stores and nice stores. If all that are in your town are nasty, it is worth it to find a nice on in the next town. Cinchers aren't cheap, but if you are going to use one, it will be the foundation of your look so it needs to be comfortable. The shop I bought mine from insisted I try it on, and she helped me get the right size. I was way off (3 sizes) with my original guess of my size. Trying it on saved me at least $100 since these items are non-returnable. When I bought my wig, the prices varied from $20 for cheap looking wigs to several hundred dollars for top of the line. I paid $70 for mine and it looks decent. I would guess average is around $100. Oh, I bought it 15 years ago or so, so add inflation!
For a store, I would go with Kohls or Belk. Kohls is a little less expensive, but the sales people at Belk have been very helpful to me. Not that Kohls have been a problem, just that Belk is more come-to-you helpful, as opposed to "I'll answer your question" (hourly pay vs. commission?). And the clientele is not as likely to be a problem at either one, as opposed to a Wal-Mart type place.
You can also try thrift stores. Look for one in or near an upscale neighborhood-it will have a better selection. I have seen nice designer clothes there with the tags still on for less than 5 dollars. You can try stuff on before you buy, but if you don't want to, it's a lot cheaper to throw away since thrift stores have a no refund policy. Usually.
Hope this helps. Have fun.