With that budget you have a vast array of basses available to you, and the quality of mass produced basses is so good now you don't have to spend a lot to get something really good. That said, there are still some dogs out there; the first Sire P8 I had was very heavy and had dodgy electrics, the second was an absolutely superb bass!
Used handmade basses like ACG, or the German Franz I am selling (see my signature below), are superb instruments, but then you can also buy a new Sire, Dingwall, Lakland. I guess the best option is to try and narrow down what you are looking for and then try some basses out. It's a nice problem to have
Good luck!