I am building a platform.When we pitched our product to client, he said, that he want all our code on his own personal server. He don't know a thing about software development but want a his own server. He think we might sell his personal data to his competitor

@Jonnyforgotten lol

Right now using aws free tier. Now each year there are going to be 250-300 new images and will be used frequently. Now he want all the images to be upload in full quality which can be upto 10MB. I told him it is going to eat up lot of space, he replied, he will pay for it. What he has not considered is, 6-10MB image gonna take lot of time to load. And in his business he can't afford that

Proper response is "Sure, on-premise start at 5/6 zeroes contract, want me to patch you up with a commercial?".

Just the number of zeroes should be enough to make him back off.

Or just be honest and say that you don't offer on-premise, if it's not relevant to enough of your potential clients.