According to my DB the lowest price is $16.99 for 170LED Solar Wall Light (in Banggood). Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
Latest coupon code price check (UTC time):
Lamp beads: 44leds/170leds, Irradiation area: 45~110 square meters, Name: Solar Projection light, Solar panels: 8W/6V, Color temperature: 8000k, Control method: remote control, Lighting time: 8~12 hours
Banggood ($16.99)
Banggood warehouse is located in China. As you can see I didn’t find any active coupon for this product right now… Good or bad price? The average price for this item is $18.89, so I think it’s a good price!
Link: Banggood product page
Price: $16.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG92199f, BG89f0e4, BGOct22LED, BGLEDNOV2022, BG589b2e
(these codes were not working in latest coupon update, but you can check them out anyway)
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
Here is price history (for all/most countries) for 170LED Solar Wall Light.
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)).