Since you're looking for a potable power station with an approx. 1500Wh capacity, I would advise not to cut corners with cheaply made units with low quality components. If you want your power station to last a long time, purchase from a reputable brand with a track record of good products and sound customer service.
Check out the likes of Jackery, Bluetti, Goal Zero, EcoFlow. Look at what you want to achieve and what you absolutely need in terms of portable power. Check out products from the above manufacturers (amongst others). Do some research and stay away from incentivised reviews that paper the cracks of the product. Then, when you've found a couple that suit you, feel free to ask the manufacturer unanswered questions or ask the community if you need help.
Preferably purchase locally rather from Alibaba. It's much easier to resolve an issue with an order or product and will save you time and money should any issues arise during the warranty period.
Hope this helps!
Techman