The idea is to make it look like a lovely place to live, but not your place. Because you don't want to live there anymore. But then, you don't want to see huge hooks on the walls, so unless there's something generic to hang there, just leave your photos on the wall, I guess. Unless there's dozens of them!

Are you going to be showing it yourself, or using a RE agent?

Have you had a look at any other places in the area that are for sale in the price range in your area? As long as yours looks the best you're probably ahead of the game, I'm guessing.
We don't have dozens of pictures - posters on the walls in the kids rooms, 2 michael jordan posters (one is like 6 foot long and goes across the loungeroom wall), a hand and foot thing of aricyn as a baby, a mickey mouse photo thingy in the hallway, a montage of kids pics near the kitchen and some wedding pics in our walk through robe.

Is that too many pics?

And we have a real estate agent.

There are 3 other units in the same complex for sale, 2 are basically identical to ours, but heaps cheaper (they are on the market for $239, ours is $255 minimum) but we have a double garage and are seperate from them, they are all joined with each other. So its like ours is a villa, not a duplex I suppose. The other one is bigger than ours, and on the market for $280.