Unique Variant maths

Hello!
I wanna get a rough idea of how much certain UVs are worth but somehow i´m too stupid to calculate. I want to see how many tries Punch will probably need to craft certain UVs.
So to get a 90% chance to have 2 specific med+ UVs on my sword, how many attempts with the 2* Ticket will i need?
Let´s assume we want CTR and ASI at least med and UVs have a chance of 1/3 to be med or higher.
How to calculate this?
Thank you very much!

I once wrote a detailed guide for UV costs at Punch. As the warning at the top says, I need to check some of the calculations. But the single-UV costs are right, and the double-UV costs are probably right too. I don't remember.
http://wiki.spiralknights.com/User:Jdavis/UVs
So to get a 90% chance to have 2 specific med+ UVs on my sword, how many attempts with the 2* Ticket will i need?
Don't do it that way. Instead buy 1-UV tickets until you get one of the UVs that you want, and then start buying 2-UV tickets, locking the first UV while you try for the other one. See the section on double-UV strategies. Your expected cost is 1,779,410 crowns.

thank you both, especially the guide Bopp linked is pretty interesting!

Maybe this will motivate me to finish the darned thing. Happy travels.
I do know a guy who got ASI and CTR high/very highs on all his main weapons and it cost him 63,000,000cr.