For your budget, get a decent(if you want better stuff, get used) 4-channel, a decent front component set, and also a subwoofer will do, skip the rear speakers, or if you want, stick wif your stocks powered by the HU.

But if your budget is 1.5k excluding install and cabling, you could work out a pretty decent setup.

For some example:
Front components: some decent 6.5" components like the PHD CF6.1(new for RM650-700)
Amp: Not too sure about this, but set aside at least half your budget for this(though i know some guy who has an Orion XTR450 for sale at about RM800)
Subwoofer: Some MTX or Kicker that works well with about 250Wrms and sealed box, i know some dude who's selling his Type-R Alpines for about RM300 each.

IMO, for audio setups, it'll only turn out nicely if you don't rush and slowly shop for good bargains(i don't call shopping from those lelong sites as bargains though, you'll never know when you actually bought authentic or fakies)

i assume it's goinna b rm1.5k for 2 front speakers (4 channel amp, 2 back speakers (draw from HU), 1 sub (draw from the 4 channel amp), 1 sub box, 1 4xchannel amp and wirings...

so every1 think it's possible huh? wif the "i want trustable, quality, durable n budget ice" statement it is still possible?? 

to me trustable ICE would b branded stuffs edi.. rm800 for a reputable amp, rm300 for a normal woofer, rm80 woofer box (if ada), wiring and workmanship would b around rm 150 and the rest r for speakers... how much would u left?

unless he said rm1.5k for component + decent amplifier then may sound reasonable to me wif his statements of "trustable, quality, durable n budget".. in my mind no cheap stuff is good stuff 

i would say get a HU around 500+/-
get a decent comp and active sub around 800
the rest for installation and cabling

ha! ha! i never know that i can listen song/radio inside the car cz my gf is   

u should start urself wif and amplifier and a component speakers.. regarding speakers, wat types of music r u heading for? i mean pop, rock, r&b ...etc...

get a good amplifier.. do u mind using 2nd hand amplifier? cz wif a new normal amp u can go for a good 2nd hand amp..

hmmm.. i think rm1.5k for all 2nd hand items might gif u a decent 1.. (i assume u r sticking wif ur kenwood mp3 HU..)

u carry ppl around wif u? juz forget 'em.. u can't hear the back speakers.. connect it to the HU and hopefully that ur unit can switch them on or off whenever u like..

Take out the front stock speaker la...
If wira front speaker good ar, no one change speaker loh...
If you have amp, the back stock can power up by HU.

You just focus on ;
Front component Spekaer,
2 channel amp(for front component) + mono amp( power up woofer) or 4 channel amp
1 12" woofer

stock wira doesn't haf any front component speakers.. i recomend u 2 forget the back speakers unless u always bring ppl around wif ur car..

rm1.5k can start ur project liao.. by it's a step by step project.. it is better to do step by step rather than doing all @ 1 shot..  cz u don really enjoy the fun of ICE upgrading.. the satisfaction u'll get can't even mention by words (for me  )

now u focus on a set of component speakers and amp first.. woofer come later lar.. bcz u can c how much of budget r u left wif 

regarding the cables.. u can use normal speaker cables and a good RCA cable from belden, monster, etc... budget them around rm200+ for 2metre o even cheaper if u can source it @ a cheaper price..

buy a 4 channel amp..

first 2 channel u use it to power ur front components
and the other 2 u use it to move ur woofer

start wif ur component first bcz it is more important than only come to ur amp.. the rest u left then onli plan for ur woofer..

try getting those components from the forum (garage sales- automotive section) o zth.. there r good quality components selling @ quite cheap price..

installation u can find our brother howiechoo.. he! he!

go for pioneer HU...

u take how many woofer???u can go my thread to see izit the same woofer n amp......u can sms me 2 discuss....welcome....haha

0126196667

hah???1 onli...then quite expensive......

the brother above u is selling magnat.. later he flames u onli then u know.. he! he!

pre-amp is for those ultra noobies.. so plz juz forget about it.. i've draw it very clear liao larhh.. i also dono where u don UN..

if it is written on the speakers it means the power that needs to run at.. (normally it's maximum) u need 2 c how much ur components need 2 power for.. (normally around 50rms watt + -) (can i call rms the pure reading o watt) i

the amp itself also is also written how much rms watt it can produce.. so if it suits.. then it is.. bear in mind that those chapalang brand amps doesn't come wif any rms especially u c those 1000watt.. it might b onli p.m.p.o watt.. (juz j/k)
i dono this brand.. maybe other sifus can help u.. hey.. i thought u haf ur mp3 player?

this was wat i used during my 1st year wif my 1st car.. HERE!

that time was nearby rm1k.. now price drop liao.. it is a good 1 for beginner.. highly recomemded for ur tight budget but yet this speakers still performs well from ordinary rm400+/- speakers..