Here is more detail, but I'm not done putting the desired apps yet on the gift phone, so, the memory needed will grow a bit more.
However, notice that there are plenty of people complaining, now that I look at every review, by LG Optimus L9 customers (model p769):
Most of those reviews were apparently put there *after* I had bought the L9 phone, so even had I known about this web page, I wouldn't have seen them in time to trade in the phone right away for the 16GB/12GB-usable Nexus 5 instead:
Anyway, I'm setting up the LG/Google 16GB/12GB Nexus 5 as we type, and here's how much space (roughly) is left after adding desired applications (before giving it to the gift recipient):
It's Android 4.4.2, which, all by itself, out of the box, (roughly) took up 16GB - 12.5GB = 3.5GB
The pre-installed apps (roughly) took up, of course, more of the space such that in usable form, only (roughly)
8.5GB of the original 16GB is actually available to the user:Note: There is no external SD card, but an sd card would only be usable for user content anyway (and not for apps).