Autosomal DNA tests from the major testing companies are typically around $99 US, but in the past few years there have been more and more sales.
Historically the best pricing in the USA has been the Black Friday sale immediately following the US Thanksgiving holiday, but other events may precipitate a sale in other countries.
In 2018, the Black Friday sales morphed into the Cyber Monday sales, which ran until the Christmas sales, followed closely by the Boxing Day sales, New Years sales, then the Spring sales, and this week we are seeing the National DNA Day (25 April) sales. I am sure that you get the picture.
The bottom line is that anything less than $99 US for a single autosomal DNA test is a good deal, but you should be able to buy a testing kit in these frequent sales for $69 US, $59 US, or even $49 US at some testing companies.
So decide which company to test with, then bide your time until you see a sale. Do not pay the full price, for the sake of waiting a few weeks.