The original DRebel and 10D were perfectly good little 6MP cameras and might serve just fine for someone on a tight budget and wanting to get into a DSLR. Cheaper 1GB memory cards would be plenty, and you won't fill up your computer hard drive as fast with the smaller image files. Yet the DSLR's images will be vastly superior to those from many point n shoot digitals, certainly any in the 5 to 7MP range, but even many with slightly higher resolution. That's just the nature of P & S, with their tiny sensors (as compared to the sensor in a DSLR). One might put the money saved into better lenses and go from there. The lens on that camera is probably the original 18-55 kit... The later 18-55 IS is an improved lens optically, but still entry level build.
I haven't looked at DRebel prices in recent years, so really don't know if $200/$250 are good or not. It was probably a $1500 camera when new! On Craigslist, though, there might be some room for negotiation to a more favorable price.
Battery and charger are the main things needed. They can be found and bought pretty cheaply, I imagine. All the other "in the box" stuff is optional or easily replaced. You can download manuals from Canon's website, as well as updated firmware for the camera, if needed, and all the other softwares. The cable from camera to computer is not essential. It's better to use a card reader... Many computers today come with some readers built in, anyway. The Canon strap is easily replaced, and often there are better (healthier) straps available from other manufacturers.
One nice thing about Craigslist is you can check out items in person (meet in a reasonably safe public place like a coffee shop or a bank lobby). The downside to CL is there are no warranties so you need to know something about what you are looking at to be able to check if it's working right to start with, and are at risk if anything goes wrong with it later on. DSLRs usually don't fail all that quickly, if they are good "out of the box" and get reasonable care, but there is a lifespan of the shutter assembly in particular... I think 300D/DRebel shutters weren't officially "rated" but probably were good for around 50,000 clicks, on average. Even with the "ratings" though, a camera might vastly exceed that expectation.... or die an early death. No guarantees.
That's one nice thing about buying from an established, used camera store like KEH, B&H, Adorama, etc. They usually check out, repair as needed, and warrant their used stuff at least for a few months. Of course you pay more for that, too.
