Laura A cheap window A/C should be 100-150 EUR I suppose. And it doesn't require any professional installation, e.g. you just insert it into your window. You can throw it away once you have a central A/C in your house.
I just checked Amazon. I only found vans in this price range. Nothing for a window. What do you mean with "you insert it to the window"? How can I insert something into glas?