So a client brought me a printed copy of a cake that Pink Cake Box has done saying they wanted that! My only thing is that I'm having issues with the sizes! At first I was thinking 6" round, 6"square, 10" round, 10"square, & 14"round, & 14"square! But I'm just not sure! I need all the input I can get!

http://blog.pinkcakebox.com/bows-and-bling-wedding-cake-2010-03-06.htm

I'm going to guess. . .16"square, 14" round, 12" square, 10" round, 8" square, 6" round. . .

The video says it was 450 servings- you could do the 'reverse' math to figure it out.
How many people does the cake need to feed?

Looking at the pic, the bottom square is larger than the round on top of it. So if that was 14 inches then the round is maybe 12 inches. You can't place a square cake on top of a round cake of the same size because the corners will hang over. So if the 2nd tier is a 12 inch round that's probably a 10 inch square on top of it. Does that make sense? If you stack your pans to see how it looks that will help you lay it out.

For my black and white cake, my base was a 12x12 but I used 4 6inch square cakes because I didn't have the larger size square pan.

That is a beautiful cake.

I'd guess that they are 6"/round, 8"/square, 12"/round, 14"/square, 20"/round, & 22"/square, which serves 12/32/56/98/157/242 = 597 (and they guessed it served 450 because they didn't do the math to calculate the larger tier servings).

You'll definitely need dummies if they want an exact replica of this setup yet fewer servings.

The right angle measurements for squares might help, if you'd like to plan another setup:

4" 5.66
5" 7.07
6" 8.49
7" 9.9
8" 11.31
9" 12.73
10" 14.14
11" 15.56
12" 16.97
13" 18.38
14" 19.8
15" 21.21
16" 22.63
17" 24.04
18" 25.46