Replying to Average Rail,Box, and Drop In cost?

Hey! Just trying to get an estimate of how much each individually costs (to buy the materials).

***Obviously each setup/rail/box will have a different cost depending on its size and materials used, so if you could please include rough estimates of the materials you used/ dimensions of your rails/boxes/setups I would be most grateful! Pics are great too!

Setup I'm looking to build:
Completely flat yard setup
OR
Portable setup to haul back and forth to the hill at my local park
(Obviously the second will be cheeper but jw costs of each.)

Rails/boxes:
Interested in building a variety of rails/boxes of various length/size so please describe/post a pic of yours!

**I know there's already similar posts showing setups with dimensions etc. but none that I found that ALL individually mentioned cost& materials used of each (if there is one please point me to it! thanks) I think we need a thread so ppl wanting to make a setup know the average cost one will take to build.

Thanks for your help guys! U Rock!!