USB Output voltage DC5V /2.1A Max, Output Voltage 220V-240V AC, Type DC/AC Inverters, Output waveform Modified sine wave, Continuous Power 3000W, Peak Power 6000W, Input Voltage 12V DC.
Go down and check coupons out. Remember to check price history if it is available. Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($61.96): BG845979
2. ($64.14): BGSCM11
just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGffa6ea, 8BGwbg2204, BG50offS3, BGAUTO22, BGdcbfa8, DealBGimpact, Cuponation9, 9OFFSUMMER, BGCarEle4, BGCarEle5
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for 3000W Solar Power Inverter DC12V To 240V. The lowest price was: $40.49.
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)).