Though as an unlit tiny station in an area of no doubt very low if any vandalism, keeping it open probably just costs about 100 yards' worth of fuel, so you might as well. People do travel to ride on obscure curiosities on lines like that.
Coombe Junction Halt does have upkeep costs - these will be to do with maintenance such as checking the help point and replacing posters, plus things like dispatch risk assessments... as well as unfortunately dealing with the odd bit of vandalism, which does in fact occur and will eventually need to be kept in check. When I was there last summer, the handset of the payphone had been torn from its cable and was nowhere to be seen, and any glass in the waiting shelter windows had long since vanished. This may be to do with the fact that a footpath runs through the station - in fact, basically two paths - and it's pretty out-of-the-way. On the other hand, you'd be right in assuming it's a simple structure. If there did need to be lighting, there is already a power supply to the floodlights for the ground frames, so I'm sure adding an LED light or three on the platform wouldn't be a great hardship.
When I walked away from the station, though, I was surprised at just how much there was in the vicinity. I hadn't really studied the maps properly, and judging by its reputation, I was expecting there to be a lane with absolutely nothing in the way of civilisation. Instead, there were quite a few houses in close proximity, cars passing every few minutes (alright, not exactly a busy road, but still...) and a few industrial units nearby.
Although access to Liskeard station from that side of the town isn't hard, there is obviously a steep hill between the two, and I think it would be prudent to consider how the facility could be improved for anyone wishing to travel to the south of the town. Unless you were to drastically remodel the railway, there's no way the reversal at Coombe is going to be eliminated, even though I believe there was possibly once an avoiding curve back in the mists of time. If I remember correctly, the rules of the signalling system in operation also makes reference to "station limits", which would be a bit difficult if you hadn't got a station!
Perhaps what needs to be done is to construct a low-cost, two-carriage platform somewhat closer to the nearby level crossing, so that the train stops within the platform whenever the reversal is done. This would shave a bit of time off the amount taken to faff around with drawing forwards into the platform, dispatch away from it, and clear the level crossing again, which isn't exactly instant. It would also mean that some risk is marginally reduced to the train crew, as they would potentially (depending on design) have a fixed platform and ramp to access the ground frame, avoiding the need to use what can be quite slippery cab steps. But best of all - the doors could be released in the platform whenever the train operates on the branch, meaning every train would call there. I am sure the local businesses wouldn't mind that at all, even if only one or two customers and staff used it. Better than the current situation!
