[st_za]

If your budget is really limited then a 1"-2" spacer lift is not a bad option because the stock springs aren't bad but if you want to be doing the type of driving where 2.5" lift is handy and considering that your JKU will spend most of its time on the tarmac, I suggest getting aftermarket springs. A good spring and shock combo also allows more flex to keep the wheels on the ground, which I have needed more than lift with type of off-road driving that I do.

You should also get longer sway bar links, rear track bar bracket, brake line brackets, bump stops appropriate for the shocks and front LCA drop brackets to make 2.5" lift handle well, which pushes the costs into a bracket where the extra cost of springs makes sense relative to the other costs.

There is also bigger or better tyres that you can consider before lift, depending on the type of off-road driving and on-road km that you want to do.

I presume that your JKU is stock so if it isn't a Rubicon, I suggest getting a front sway bar disconnects and also a steering stabiliser flip kit and an aftermarket rear diff cover as your first modifications. Lift doesn't mean anything when a rock peels open the rear diff.