When I was updating this page the price was $18.99 for JSD-520 Bluetooth Car Audio Player (in Banggood). Price history, coupons and price alert are available on this page. Do you want to know what the best price is?
MP3 / WMA / APE / FLAC / WAV, Preset 18 stations (frequency: 87.5-108 MHz), Bluetooth Specification：V2.0
Latest price update (UTC time):
Banggood ($18.99)
Banggood warehouse is located in China. There are no coupons for this product in Banggood. Low/high price? From what I can see this price is higher than average price ($17.99).
Link: Banggood product page
Price: $18.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGSCM11, BGCarEle5, BGLMQ15, BGAMMT03
(you can check these old coupons out, but these probably won’t work)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for JSD-520 Bluetooth Car Audio Player.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).