When I was updating this page the price was $29.99 for Car Head-Up Display OBD2+GPS Smart Car HUD Gauge (in Banggood). You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
Latest coupon and price update (UTC):
Car Head-Up Display OBD2+GPS Smart Car HUD Gauge Digital Odometer Security Alarm Water Temperature Alarm
Banggood ($29.99)
Banggood warehouse is located in China. There is no active coupon in my database right now (for Banggood). Isn’t it too expensive? It looks like it’s a good price (lower than average ($30.49)).
Link: Banggood product page
Price: $29.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG22e216, BGAMMT03, BGd158d8
(there’s a little possibility that old coupon will 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 Car Head-Up Display OBD2+GPS Smart Car HUD Gauge.
Price records source(s): 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)).