First Id look used. Ibanez makes a decent starter bass (SR or something like that). They sound pretty good and usually well built. They have skinny easy playing fast necks. Lots of em out there on CL, eBay, and everywhere, sorta like Affinity Strats. You should be able to find a decent one for $100-$150. Deans are another GC brand in this category. A used Squier Standard P or J could poss also be found.
If your want new, agree SX are a good deal. May require some set up tho. So figure in a likely set up and possible fret or nut work, poss a scratchy pot, in the equation. After some tweaking tho, good as a Mexican Fender IMO.
As long as it's comfortable, stays in tune, the electronics work, and it goes "thump" is all you really need to worry about. Then get as big an amp as you can afford. Id look used there too. An old Peavey TNT is cheap & powerful, but heavey. But your young. Get a stack if you can.