"Expensive" operations

Does anyone know of a good source to review regarding how “expensive” different elements on a form are?

I have a web based solution that I would like to make lean and mean so I would like to stay away from “expensive” operations on the most heavily used forms.

I realize a general thumb would be the more data displayed, the more “expensive” but is there a difference in how the data is displayed?

Tab panels vs portals?
Hiden Tab panels vs regular tab panels?
Custom controller vs non custom.
Tips to downsize data transfer?

Jim

I am also looking for any excuse to type “expensive”.