To find the price per volume of vodka (or any liquor). And compare it to other brands to find the best value for your buck. Just follow a few steps:

Steps to Calculate Price Per Volume

Find the Price: Determine the retail price of the preferred distilled spirit bottle you're interested in. This can be done by checking online retailers,
visiting local liquor stores, or consulting the brand's official website.

Note the Volume: Check the volume of the bottle, usually listed in milliliters (ml) or liters (L). Common bottle sizes include 750ml, 1L (1000 ml) and 
1.75L. (1750 ml).

Calculate the Price Per Unit Volume: To calculate the price per volume, lets use 100 ml as an example. Use the following formula: 

Price Per Unit Volume = ( Total Price / Total Volume) * Unit Volume

Example: If a 750 ml bottle costs $20, the price per 100 ml would be:

($20 / 750 ml) x 100 ml = approximately $2.67 per 100 ml

Now that you have the figure for your preferred Choice, You can move on to the next step.

Compare To Other Brands

1. Repeat the Process: Do the same calculation for other brands that you're interested in comparing with.

Let's say another brand you were interested in, does not have their 750 ml bottle available. They only have a 1 Liter. 

1 Liter for $26, the price of 100 ml would be:

I need to change Liter into mililiters which is 1000 ml.

($26/1000 ml) x 100 ml = Approximately $2.60 per 100 ml.

2. Compare Prices: Compare the price per 100 ml  for each brand. This gives you a direct comparison of how much each brand costs relative to the 
volume of liquid you get.

Preferred brand cost $2.67 per 100 ml.

Alternate brand cost $2.60 per 100 ml.

As it stands the alternate brand is a better choice to get the most out of the money you will spend. Although you want to consider other factors before handing 
over your cash.

3. Consider Other Factors: While price per volume is important, also consider factors like brand reputation, quality of ingredients, production methods, and flavor profiles. Once you have all the facts you can then make your final choice.

4. Use Online Tools: There are online tools and websites that can help you compare alcohol prices. Websites like Wine-Searcher.com or 
Liquor.com often have features to compare different brands based on price and other factors.

5. Read Reviews: Look at customer reviews and expert opinions. Sometimes a higher price per volume does not necessarily mean better quality.

Remember, prices can vary significantly based on your location due to factors like taxes, import duties, and retailer markups. Always check multiple sources 
to get a good average price.