As you develop as a player (and dare I say your tastes change with age) your kit will change / you will not get what you need from it - this is a personal musical evolution we all go through. Its part of the hobby/passion/profession.
Most of us have flipped loads of kit, some of us are now happy (for now, anyway
), I regret selling one or two of many guitars flipped - but none of the amps.
As mentioned - Buy the best you can - but the "your sound" of the title, is your feeling and memory of your "Current" tone search - try and work it, but don't die in the attempt - if you go back in a year, the sound you thought you heard won't sound the same then - you'll have a new "my sound" !
Hope that makes sense - Good luck.