I plan to fit wheels, such as appliance wheels (of the sort used to move fridges and washing machines, etc), or buy a garden trolley and convert it into a scope dolly, to the base which will definitely make life easier. But I have to ensure I buy wheels, or a trolley, with some sort of brakes on or it'll be moving all over the place when I am observing - no use whatsoever!
I am also going to need some sort of dew control, such as a lightbulb or low watt heater, which I can run off a car battery charged by a solar panel. I have had one mirror's coatings wrecked by condensation and mould, which will cost me around £135 to get resilvered and I don't want a repeat of that!
The top of the garden is a bit too close to the neighbours for my liking (a couple of houses; we live across a footpath from them) and one house has a couple of kids who climb the trees and can overlook the garden, and I don't like that, but the observatory won't be directly beneath that tree. However, the hedge, and fence beyond that, plus the oak trees in the neighbours' gardens, are high enough that there'll be no significant light tresspass from any houses, even in winter because the hedge is a mixture of evergreen and native plants. The top of the garden also has good views of the south and south east, plus I can catch stuff rising in the east (over the house but you can't have everything - and the garden's huge, so the house is actually not much of a hindrance and the light trespass from it won't be as significant as it is now, when I observe from the patio). There is a large tree obscuring part of the south east sky but the harsh winter this year killed it and it is due to be cut down at some point, when we can find an alternative place to hang the bird feeders and fix one end of the washing line.
Potential theft is a concern but I will make the shed as thief-proof as humanly possible and I am not going to keep anything of any value in there, beyond the telescopes - eyepieces, etc, will be stored in the house. I currently use a cheap scope and, frankly, it and the others are not worth the effort of pinching them. Besides, any would-be thieves will have to carry an insanely heavy instrument a long way down a large garden and get past three dogs who do not tolerate strangers or intruders.
The shed is ordered and should turn up early next month and we can get it put together while the weather is good.