you can always use a dumbell AS a "perfect pushup" handle, so there is one less thing to buy (since they normally come in sets of two)
There's a few more directions you could move them dumbells; namely, above your head. I start out with a curl, and then go into an arnold press, for a more complete compound movement - basically a clean and press, but with dumbells
For a pull up bar, since my walls aren't strong enough, I just built one out of 3/4" steel pipe and 90 degree connectors from the hardware store. Pad the bottom with inner tubes, lean it against the wall, and you have a no-hole-in-the-wall pull up bar, perfect for renters