If you are on a budget you will be hard pressed to beat a 2007 or earlier Ninja 250R. An older GS500 or Ninja 500r may come close. These “entry-level” bikes are easy to find for under $2k and are very capable street bikes. An SV in comparable shape will usually be well over twice the price.
If you get a good deal then it won’t be hard to sell for what you paid if you feel you have to upgrade.
Budget reasons for getting a bigger bike just don’t really make sense. Even if you do get bored with the smaller bike in less than a year you will still likely come out ahead because you can put off the bigger expense and you won’t lose much on your first bike.
And if you are getting bored on a Ninja or GS in less than a year you probably are not riding the bike hard enough.