How much do i request as a tip for a crafted item after prices for orbs and any mats i have to acquire
If it is a tip.... you don't request it.
Yup if you ask for gold it's a fee, not a tip.
Just because you can doesn't mean you should.
Indeed, tipping is a custom, but it doesn't mean people have to do it. The word you're looking for is fee. Depending on profession, difficulty in getting the recipe and so on, I'd say anything from 10g (learned from trainer) to 200g (rare drops), there are certain exceptions of course where you can expect a huge fee from, but the aforementioned are for Cata crafts.
As stated, one does not request a tip. If you request any sort of payment for crafting something, it's a crafting fee. A tip is something a person gives on their own accord.
Depending on what is being crafted though, I may tip anywhere from 10-100+g. The most common things I have crafted are cut gems, and I usually tip about 15g on top of supplying my own gem. But if it's one of the rarer cuts, like the new int/crit damage meta, the tip goes up because of the rarity of the pattern. It's rare for me to have anything else crafted though because I get my enchants from a friend as well as tailor-made gear. But on the rare occasions I do have to have a non guildie make something such as a belt or boots, my tip goes up significantly, just because it's a more powerful item being made and not all tailors have them just yet.
first look up what a tip is and you have the answer.
I give the amount of a cata quest reward, minimum , for common recipe
But , anybody had an idea how much I should pay for crafting the vial of the sand drake ?
Most people who have the vial will have a set charge. Most often I've seen on my server is ~3k, but some will probably do it cheaper now (not a lot advertise for it, since it is so rare, but I know quite a few ppl have it so I imagine price has gone down).