Dear @jinshu1987
Thank yo for your offer, we never charge from our valuable buyers more then cost, we just make quote in tight budget, because of we think buyer will happy to get own features.
Our working hours cost will not be below then $400 USD, So we can do it for $400 with your mentioned features.
Let us make clarification about exclusive license for your features
We can guaranty about Point 1,4,5 that it will not come any future update.
But Premium campaign is in our plan, we may introduce it or not. it’s 90% sure that we will not include it, if any how we include, it will be not your coding, we will introduce in another way but not yours feature, though it will not soon ad possible is just 10%. (It’s just a condition in our favor)
If you confirm us, then we can start after end our vacation. Feel free let us know
Best regards