Got my first wedding cake order. Yes, I'm going to have lots of questions. Question #1) what sizes do you think these tiers are?

looks like 6, 8, 10 . Did they not tell what sizes they wanted?

They might be 12/9/6 - it looks to me like there is more than a 2" difference between each tier. But what really matters is how many servings you need. That will determine what sizes your cakes need to be.

yep that is what I would say too. You need to ask them how many they need to serve and what sizes they would like though.

Well I know that they need 75 servings which would be a 6, 8, 10 but she showed me a picture of this cake and to me it looked to be more than a 2 inch difference in layers, that is why I was asking.

She also wants the detail to be in black. Question #2) should I do the detailed black in royal icing or buttercream? Question #3) will it bleed into the white if I do it too soon?

Thanks.

A picture of a cake is to give the baker an idea of the design. A realistic bride does NOT expect her cake to be exactly the same dimensions. (If she does, she's a twit and it's the baker's job to educate her.)

But the difference of 1" on the tiers of the cake is not even distinguishable.

It doesnt' matter what size the cake in the picture is. You need to make the number of cake servings she needs .... not the number of servings someone ELSE made and photographed.

What are you icing with buttercream or fondant?

If it's fondant, pipe with royal icing.

If it's buttercream pipe with buttercream. Piping royal icing onto buttercream will 100% bleed as the moisture in the buttercream affects the royal icing.