Ok so ive read probably 1000 issues similar to mine and I want to make
sure of what I do before I try, considering my situation... Heres my
story... Last year I noticed my car (usually in the mornings) would
have a slugish startup, after about 3 days of this my car finally cut
out while driving on the beltway @ 65 mph, I managed to get to the
shoulder.. My brother came to give me a jump and it works, about 1 mile
down the road it dies.. Jumping it only works untill I take the cables
off then dies right away so I replace the alternator AND the battery..
ok so everything is sweet! Its like this for about a YEAR and suddenly
my car is doing it again, with the slugish starts. Right now I have a
battery and alternator thats less than 1 year old and my car wont start
at all, even if I jump start it.

1. Put in key turn to Acc. everything bursts into normal functioning
order. Full brightness, dome light on, stereo comes on. (even before
attemping a jump start, so it appears battery is at full charge)
2. Turn ignition to start, ONE click sounds. But it isnt turning the
engine, just one simple click.
3. I dont have a volt meter so I dont have any way to test the actual
voltage, but when I use any electronics it does not dim at any time
during jumping or turning the key without jump start aid.

So what would you suggest I do in order? Im guessing from what I
gathered abroad that its the starter/selinoid (which I understand is
also hard to access). My car is stuck at the bottom of a pay to park
garage so I would like to get it working asap.

Also 1 more thing to note, maybe its coincidence but the slugish starts
happened about the same time I had a headunit cd player installed via
best buy. Before that there wasnt a stereo at all. Also to  note, I did
try unplugging all fuses and uninstalling the headunit thinking maybe
there was a short... Same thing as before so its most likely not the
headunit.