I have probably tried more types of commercially available limoncello than anyone alive that doesn't work for a limoncello producer. Unfortunately there are no official awards for this type of achievement so patting myself on the back will have to do. The benefit to you is that I can definitely tell you what it costs to buy and to make limoncello.
A bottle of limoncello purchased at a store will cost about $20 USD. The exact average of 17 different brands was $19.25, ranging from a low of $13.99 to a high of $24.99. Making limoncello at home is cheaper if you don't count labor, and much more expensive if you do.
The quality of store-bought limoncello is highly variable in my opinion so that same twenty dollar bill can provide you a better or worse experience depending on which brand you choose. It's counter-intuitive because limoncello has few ingredients, but the quality of those ingredients matters a lot. See my reviews for more info on this.
To get an exact and current figure, I pulled prices for all the brands I've reviewed that are still sold plus 10 more that I plan to review in the near future. This is a snapshot of prices from the web as of 1/19/19, but limoncello prices don't fluctuate much over time. All prices are for a standard 750 ml bottle and all prices are in US dollars.
The overall average price for a bottle of limoncello is $19.25 and most of them cluster right around the $20 mark. Fabrizia and Morey are particularly inexpensive, which pulls the average down a bit from $20. Fabrizia is likely cheaper because it is made in the US, whereas most brands are imported from Italy. Morey is made in Spain, so I'm not sure why it's so cheap.
Price per 750ml Bottle
Sogno Di Sorrento
Ventura County Limoncello
Limoncello Di Capri
Vincenzi Limoncello Di Torino
If the appearance of the bottle itself is a factor for you, definitely check out all the different brands. Some have much cooler packaging than others. This isn't really a consideration for me--I only care about quality--but to each his or her own.
If you want to make your own limoncello at home, you are to be highly commended. That's the kind of initiative and self-reliance we see far too little of these days! But seriously, I've got plenty of advice for you on this site. However, the question at hand is about the cost of the DIY method vs. going to the liquor store.
I've calculated that a bottle of my own DIY limoncello costs about $8.80 to produce. That is lower than any of the prices above, but it's not comparable either. It omits any labor costs, which are substantial. Making limoncello is a labor of love that you pursue because you want it to suit your particular taste, not to save money. It also excludes the cost of the equipment you use. I don't think that's a huge deal because the equipment can be reused for many batches and there's not a lot of it anyway.
It's up to you! I have provided some reviews, and plan to produce many more. This will make it easy to decide when you go to the liquor store. The store I patronize has quite a lot of limoncello variety but that's highly unusual. The average liquor store you see in a strip mall has a very small selection, usually three or fewer varieties.
At the end of the day, you're drinking limoncello. How bad can it be? Definitely worth one Andrew Jackson if you ask me.
Q: Where can I buy (fill in the blank) brand of limoncello?
A: If you live in a state that allows liquor sales by mail, the world is your oyster. BevMo and other large online retailers can usually get you about anything you want. If you don't live in such a state (like me), then you're limited to what you can get in stores near you. There are huge wine and spirit outlets around like Total Wine & More though, which have large selections as well.
Q: Why are prices near me so different from your prices?
A: My prices above are internet prices, which tend to be very competitive. I have been to many specialty stores and have seen bottles of limoncello selling for $30 or more. This is because they don't move a lot of bottles in those stores. Limoncello doesn't last forever on a shelf so for a couple reasons, those stores aren't a good place to buy.
Q: Can you send me a sample of your own limoncello to try?
A: No. Like my limoncello, this site is a labor of love that costs me money every month. I won't be trying to scale that deficit by sending out samples...