The two features on your list
will be the challenge for your price range.
"good low light" = large lens filter diameter to let light in to the camcorder's imaging chip and a large imaging chip to deal with the light that is allowed in by the lens.
"clear audio" = the audio source (your voice, at a normal audio level) needs to be close (within a couple of feet) and in front of the camcorder's built-in mics. If you are behind the camcorder - hence behind the mics, audio quality will not be as good compared to when you are in front of the camcorder - and in front of the mics... but that proximity may not frame the shot you want so an external mic would be desirable.
If you do a bit of investigation, you will see inexpensive video image capture devices start at around $100. Small lenses and imaging chip. As the cost of the device goes up, the lenses and imaging chip get larger. Then the audio-input jack appears... then manual audio gain control... then external manual controls for focus, zoom... and later, manual audio gain control on the outside of the camcorder.
For your price range, take a look at the Canon HF M series. Use a tripod. Use some video lights (like worklights from the hardware store). Search "inexpensive video lighting" at YouTube, pick a few and pay attention.
We hope your computer has the horsepower to deal with the AVCHD-compressed video. And hopefully, your video editor can deal with the MTS or TOD files, too.