Knobs and switches at the front of course. Yes, if using an aluminum rod extender for volume pot, this layout may not work, without a rod, it might but the wires will not be the shortest. I use 7" long shielded cables in my preamp into the volume pot and there no artifacts to SQ that make me want to change it. Lets wait for Siva's opinion.
I'd keep it simple and have only the power switch and LED(s) on the front panel, since this is a pure power amp. Volume control can be retained as a pre-amp or source function.
However, those who want to use a LightSpeed attenuator or just a plain ganged pot may want a volume control on the front panel.
Regarding pricing, the MyRef monoblocks are Rs.1.5k each, firm. The Trafo can range from Rs.500 to Rs.3k, depending on whether you want EI or toroidal, and the VA rating. All the rest is going to be chassis components, heatsinks, connectors, cabling, etc., for which the pricing can vary greatly depending on size, finish, etc.
Heatsinks at Amar Radio: They're extruded aluminium heatsinks from Success Electronics, Maharashtra. The largest ones are SE205, SE215 and SE270, where the number denotes the length (longest dimension) in mm of the heatsink. In the context of the design posted by Quad, that would be related to the Depth of the cabinet.