A rear antiroll bar is £150 and coilovers are £500+ On a budget Id start with a rear arb. You only need to replace balljoints, bushes and trackrod end when they break, these are toyota not shit french peugeot. Standard na, as the title says, will understeer like a bitch. Just fitting a rear arb makes it neutral with light oversteer on the tightest setting. I have standard shocks, standard springs, 13" skinny tyres, 14 year old balljoints and I can sit with any midern car over any road and around any corner. I also have a full interior and can take speedbumps at 55mph. I would start with a rear arb...