Design a sequential switching circuit

job is quite simple, design a schematic & PCB (ready for manufacturing) that will sequentially switch with momentary push button. Each press of button will move to the next 'relay' (could possibly use transistors, as all loads are DC however needs to be rated up to 5A each) and close the previous one. There should be an OFF button also, which is also momentary and shuts off power and returns back to start position. Option for a RESET button, which will return the sequence back to relay 1. Should be expandable, first module will be 4 'relays' and ability to plug in as many additional 4 relay boards to continue sequential switching to expansion as large as want (up to 20 would suffice). LEDs will illuminate to let you know which relay you are at in your sequential movement along them. 1 additional feature is an automatic switch, which is powered by a solar panel - when the voltage drops to a certain level (ie. no sun, and it's night) this will flick a relay to the on position and thus automatically switch on a load. I have some outline drawings of what I am after, which can be provided to the winning bidder. I also have a couple of products that are close to what I want, but just need tweeking to get there. These can be shared in due course. Basically, this is a circuit to replace a physical rotary button, or multiple on/off toggle switches with a single push button (pressed multiple times to switch each stage) with a couple of extra features. Should be 12V powered.