DC wiring on shelf layouts

[tsby_fan]

I'm working on the technical aspects of my shelf layout, trying to plan ahead for the day work begins on the layout. One of the problems I'm facing is wiring- I plan to use DC(as DCC is not in my current or future budget) and as the layout will be a shelf around the room, in the shape of a folded kidney bean, how do you do the wiring for blocks that may be 40-50 feet away, wire-wise? Do you place the power packs centrally and use tethered throttles? Some kind of booster, like in DCC?
TIA,
Al