You can create price alert here, copy coupons and view price history. What is best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Charging Time: 4-6 Hours, Battery Capacity: 48V 15AH, Plug: EU Plug, Maximum Grade: 40°, Tire: CTS 20″*4.0, Assit: Five gear assist, Display: S866 LCD Display, Bottom Axis: Sealed bearing bottom shaft, Transmission: Shiman0 7S speed, Brake: Mechanical disc brake, Mileage: 110km PAS mode, Shifting Lever: TX50R, Front Fork: Aluminium and iron mechanically lock the fork, Net Weight: 27KG, headlights, Pedal: Aluminum pedals, Battery Type: 18650 Lithium battery, cruise control, Top Speed: 45km/h, brake power off, Packing Size: 95*47*80cm, Certificate CE, Model: R8, 70km Pure Eelctricity Mode, Other Functions: Horn, Rear Derailleur: TZ500, Chainring: 48T chainring, , Gross Weight: 32.5KG, Frame: 20in Aluminum alloy frame, Motor Power: 48V 500W Brushless Motor, Payload: 150KG, Color: Black
Banggood
Banggood warehouse is located in China. We have found one coupon for this product!
Link: Banggood product page
1. ($1127.99): 7bcdf9
apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGEBSC15, BGwhielabel
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for R8 48V 15Ah 500W Electric Bicycle? There we go.
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)).