I have just checked coupons. The lowest price I could get is 13.66 USD for Mini Analog (in Banggood). You can create price alert here, copy coupons and view price history. Let’s see what best price is ATM.
Latest price update (UTC time):
Banggood (13.66 USD)
Banggood warehouse is located in China. Well, is it a good price anyway? Pretty sweet, this is the lowest price I have ever noted for this product! There is one coupon right now! Check this out.
Link: Banggood product page
Price without coupon: 15.52 USD
Coupon (13.66 USD): BGPlane12
(CouponsFromChina.com tip: apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop)
13.66 USD – This is the best price ever noted in my database!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): Parts8, BGRCParts8, MVC8SPRING, 8BGwbg2204, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BG8RCToy, BGToys1, BGRCT10, BGJUNEGSG9, BG00c906, Cuponation9, 9OFFSUMMER, BGMatt2022, BGToys8, BG589b2e
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – 6 pcs. SG90 Mini Analog Gear RC Servo [EU] (-3 USD)
Aliexpress
Click here… to search for 6 pcs. SG90 Mini Analog Gear RC Servo on Aliexpress
Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for 6 pcs. SG90 Mini Analog Gear RC Servo.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).