Cherries chairman Eddie Mitchell said the Palace offers started before the game, continuing with another during it and a rejected bid of £500,000 at the final whistle.
Mitchell told the Bournemouth Daily Echo: "We had some verbal offers for Danny from Crystal Palace and they were all turned down.
"I had one phone call before the game, one at half-time and another one following the final whistle.
"The figure went up as the game progressed and was £500,000 in the end. It had started a lot lower than that.
"I told them he would cost £1m-plus and said he would not be going for anything less.
"I am standing firm on this one and there is no room for manoeuvre."
Ings did not score but his side won 3-1.