What music do you play? Do you have a good amp?
In a 15k budget you can get about maybe 5 stompboxes at the maximum. You'll have to prioritise what effects you want. EQ, Compression, Overdrive/Distortion/Fuzz, Delay, Chorus, are just part of a long list. Each stompbox has it's own sound so if you're looking to emulate multiple artistes as close as possible you might not be able to do that with a single stomp for each effect. You can't get Dave Mustaine with a Boss DS-1, or Dave Gilmour with an EHX Metal Muff.
This isn't to discourage you but it's necessary information and something to consider while making the choice.
Everything's Eventual (tm)
Scarborough Fair/Canticle (Cover)