Maybe a dumb question, but what do you mean by its in a conservatory? Also, I know this question just came up pretty recently, go back through a few pages and see if you can't find that post. I know it also had a link in one of the replies to even more tips on moving a tank! Good luck!
Heres a plan....
I bag fish plants up etc,
Put the water in 25 litre barrels,
remove gravel,
take tank off stand,
take stand upstairs,
Place tank on stand in new place,
Put the water in,
Put the plants backin,
Leave for 5 mins,
Slowly float bags o fish on surface for 15 mins.
That sounds fine, it should not be too hard since it is a smaller tank and you are not moving it very far. Depending on the size and number of fish, and how quick you can be, you might even be able to just put them in large pitchers or a couple of containers and not worry about bagging, but whatever is easier really.
Sounds good. Just be aware of Temperature swings. he water will probably cool down quite a bit during the move. Don't have a specific idea to adress that.