I was asked to make a cake for 50 ppl and I was planning to use two pans of 6 and 10, 2 in each to make it a 2 tier cake of around 4 in each, however, the client does not want any filling.  What would u suggest?  does it look okay to use two pans of the same size with no filling?  I would like each tier to have some height and I do not have 3 in pans so I can make just one of each. Any ideas pls??? 

You obviously are going to have to use icing somewhere (like the outside), so would your client be ok with using that same icing as a filling, rather than another type of cream or fruit based filling?

Oh cake muggles. Tell her it needs butter cream in the middle. Just don't call it a "filling". 

If they want a stacked cake, you need to put something in the middle to make a decent sized tier. Otherwise it would look like a deflated cake.  Would they be okay with a sheet cake?  You could put 2 squares side by side if they don't want filling. Who doesn't want filling??  Cost wise?
 

The cake is for a friend of a friend so I haven't really talked to the client but she only told me that she does not like filling.  I will try to use 3 in pans and use a parchment collar to make them look taller.  Lets see how it goes.  I do not have sheet pans and do not want to expend extra money purchasing one now since I only bake on my spare time.

AI have had many, many, MANY customers tell me they don't want filling. What they mean is they don't want a fruit/custard/etc filling. When I explain that ALL layered cakes ,anything other than a flat single layered sheet cake, have at least buttercreme in the middle as "glue"between the layers, they ALL say "oh, yeah, that's what I meant. Just buttercreme." Seriously. Don't try to stack a tiered cake just layer after layer of cake. Explain to this person. Unless they are completely clueless and really do want a bland plain, completely naked, unfrosted and undecorated cake.

Call the client and ask her exactly what she means by "no filling". 

And if they do want a completely naked cake, I'd suggest a pound cake baked in a Bundt mold.