If I purchase any bottles, they come with great beer in them. Any microbrew you can find, with few exceptions will be in capaable bottles, all you need to do is soak them in oxyclean and the labels will slip off.
Even some macro beers come in crown rather than twist off bottles. One of my favorite is Bud American Ale bottles, they have a unique shape, the beer is not as nasty as their other products and it's cheaper than most micros.
But there are plenty of options for homebrewers that don't cost anything.
It seems at first that accumulating bottles is difficult but if you mention around to people that you brew and need crown bottles they will start showing up. There's also craigslist, and freecycle.org, hooking up with other homebrewers, recycling centers. Asking at beerstores that have a good selection of beer for their returnables. Some stores will let you have their empties for the price of the deposit. And some bars will give you all you can haul out if you ask.
Also if you want to bottle in champagne bottles, go to a hall that does weddings, heck even a moose or vfw hall, you might just have to dumpster dive at worst, or just pick cases of empty asti bottles by the back door.
It seems daunting but you'll get plenty really fast. But in reality when you annouce you are homerbewing, they do come flying at you. I even had my building sooper years ago just use his key and leave me some on the dinning room table. He knew he'd get beer from me on a regular basis, especially if he was gonna do some work in my place.
As to flip tops, those work great, most Homebrewer's I know covet Grolsh bottles, even going so far as to maybe actually drinking that nasty stuff. You can get replacement gaskets for them when they start to wear out.....But you don't need to do that right away...Because if you are getting them "new" they've only been used once.
And as to heavy cardboard beer cases they are fading out. You can still find them for bud products (just go to your nearest beerstore and ask for them, they have them piled up in the store room.) But they are really overrated. The best storage I have found are milk crates. I stopped using cardboard boxes them years ago, a milk crate can hold the same amount of 12 ounce bottles (24) in half the space. Plus they stack nicely.