For some people a 5% to 10% down will help a lot but most people don’t have the income or savings so they take the 5% kick back and put is as a down payment.
So the house sells for $500k. The buyer needs $25k for a down payment. The seller then says I will sell it to you for $530k, give you the $30k needed as your down payment. The seller gets the $500k they wanted and the buyer gets the $30k they need and only gets a loan for $500k which works out the same for them. They won’t pay more in anything but property tax.
It is a back door method of getting the home you want. An old realtor played this same game with me. I told him there was this house i wanted for $700k but cannot afford the taxes, closing fees and down payment. He said he will get the seller to sell for $750 and the seller will pay my down payment and all fees. This guy was SLEEEEEEEZY to say the least.