Girl noobie
 

Hey guys so I need some help upgrading my sound system in my car. I know only the basics when it comes to this so bare with me please. Any help is appreciated! I mainly want alot more bass added on. So I'll need a subwoofer. But I guess first i need to buy the aftermarket radio and dash kit. I want something nice but not too expensive. What would you guys recommend? Navi would be nice but its not a must. I tried searching online for some but only a few options pop up. What size should I be searching for in terms of the radio? Again, sorry for my ignorance guys :) This is just something I really want to do myself and not pay someone to do.

Welcome to FF's Evie. What year is ur Fit? Here check this unit it's from rep. co. Crutchfield head unit , still need amp and up graded speakers, ....$ :)
http://www.crutchfield.com/p_130X270...H-X2700BS.html

MzFiT:

https://cimg9.ibsrv.net/gimg/www.fit...b0f82ca6d4.jpg

The radio really depends on your needs, a single or double DIN unit will fit in the Fit. One thing you should look for are pre-volt outputs. You are going to want 3 pairs (Front/Rear/Subwoofer) this will allow you to hook up your stereo to amps very easily. Aim for 4 volt or higher pre-outs if you can, but this isn't critical. Try to go with a well known brand as well, Alpine, Pioneer, Kenwood, Blaupunkt, Clarion.. You will find cheaper radios available, but you definitely get what you pay for when it comes to car stereo. Also, make sure when you get a subwoofer that you get a box either made for that sub, or read the manufacturer requirements for enclosure space. You don't want a sub in the wrong size box, your sound will suffer. Lastly, get an amp that is rated correctly for the sub and has the correct RMS power. Incorrect power will cause your amp to turn off and possibly blow out.