I had 6 weeks of annual leave saved up. Im changing to a job that pays significantly more than my current salary. When my boss asked me what it would take to stay, I asked for a salary increase of 35% which he begrudingly gave me. Then I quit. This equated to an entitlement payout of about $10,700 instead of $8000 on my previous rate, an extra $2700. And the new job still pays more than the increased rate I asked for.
Alternative take. Fight hard for a promotion, of course if you can get a raise and promotion that is ideal. But usually companies get hung up on money.
If you can’t get both don’t hesitate to say, "I just want the title I don’t need extra salary or anything. We can even take some of the extra work I’ve been doing and make them a normal part of my key responsibilities. "
Then as soon as you get it start applying to new jobs with that as your title. New jobs will always pay you significantly more for your new better title than the 2k or so you would get from a raise. I used this trick to triple my salary over 6 years, moving through a few jobs and from a receptionist to a Sr manager.