I use three different sizes of bottles for my hot sauce; a 5 oz. woozy, a 10 oz. woozy and a mini for free samples. My recommendations are to start with a standard shaped bottle that you find most hot sauces come in.
For marketing purposes a unique shape to your bottles will make it stand out but will cost more to manufacture. Most sauces are sold in a standard bottle shape to make it recognizable as hot sauce. Its the flavor of your sauce that makes it stand out.
Glass Bottle Outlet
5 oz woozy bottle with the cap and reducer for. Perfect for small batches, promotional sales and giveaways. Less than $.40 each if you buy 8 packs of 24 (192 total).
Check out price and more products at glassbottleoutlet.com.

Amazon
Everyone knows Amazon has a ton of products and merchandise to include a great collection of hot sauce bottle, both traditional and unique. I have had an excellent experience with Amazon’s shipping prices and policies.
Check out the latest pricing for 12 oz woozy bottles.
Walmart
Here are the mini bottles to be used for samples or promotions. Walmart has a case of 50 for about $.85 each (plus shipping). At 50 ml each they can provide just enough sauce to make taste buds wanting more.
Check out hot sauce bottle and other supplies here.