Is it one of the houses you photographed then decided to move into? 
You're much nearer the truth than ye think

I'm with you though, on the 'leave as is' idea. I've done that here. Where I've had to add, I've done it sympathetically to the original. Had all the windows replaced ~ original style, of course ~ and am now going round the insides, finishing in the reveals. But, I'm deliberately not doing my best. I walk away before I'm finished and even engineer the odd, 'artistic' slip of the trowel. Which I then fail to notice or make good.
Result is that it matches the original work and what's become of it over the years, see? Bit rough and craggy. And, when I'm done, I'll not be bringing a tin of Brilliant White near the place! I'll have 'Dirty, Old White' mixed for the job.
My favourite little anecdote is about when the lady who was born here, about eighty years ago, dropped by. I was showing her the cow sheds and she was just saying, " And we used to have a little gate. Just ..... Oh!
there it is! My Father made that

"
Of course, I didn't mention that
I'd made that one. Taking my cue from a couple of splinters of decayed wood and some bits of rust. All that I'd found left, a century later. But that did it for me. Made my day to see her completely convinced that not a thing had changed here
