Speak to whoever is the utility supplier for the properties - the meter is their property and they will charge you to move it and they usually take ages over doing it.
When thinking about whether to keep the supplies split or unify them - I'd say in part it depends on how much work you're intending on doing. Do you intend to have 2 totally separate heating and lighting systems? If you're re-doing heating/plumbing and electrics I'd unify them. I'm assuming you're decades away from being in your seventies? <just a guess> It'll all need another overhaul by then anyway!
DH and I own the two flats that were once an Edwardian house, and have lived in one of them for 10+ years. We also own the freehold (a separate purchase).
We are finally in a position to convert the two flats back into a single dwelling! The conversion itself shouldn't be too complicated from a structural point of view given that it is only a piece of plywood that separates the two flats - according to next door neighbours who have lived in their place for eternity, our conversion was done about 40 years ago.
Something that does look like it will be more complicated is the issue of utility meters. At present one of the gas meters is in the middle of the upstairs flat, in a titchy cupboard in the corner of DD2's bedroom. It backs onto the bathroom wall and the landing/corridor. The other gas meter is is the cupboard under the stairs and is fixed to the wall that adjoins our neighbour's house. It is sitting on a ridiculously sharp metal shelf that is cleverly positioned about 15cm from the cupboard door at the sort of height that would take out an eye if anybody were to ever try to retrieve something from the cupboard.
Meanwhile, both electricity meters are in an inconvenient position behind the front door (in a hideous L-shaped cupboard that prevents the front door from opening fully). The upstairs flat's fusebox is in this cupboard too whereas the downstairs flat has its fusebox in the cupboard under the stairs (opposite the gas meter). I'd like all of these returned to their likely original position above the picture rail in the hall, like most of the other properties on the street.
We're not particularly bothered about combining the gas/electricity supplies for the flats as DH has lofty ambitions to reconvert the house back into flats when we're in our 70s and to make millions when we sell the two separately.
I'm not completely sure who we should be talking to about moving the gas meters to outside the house. The Transco website (we're in South London) isn't that helpful for our situation i.e. there isn't a page entitled 'what to do when your gas meter is in the middle of the house and you want it moved to a more sensible location'.
Any ideas/advice would be much appreciated. Thank you!