I'm current expecting #2 and all being well the age gap will be approximately 20 months. My mum has told me to not waste my money on a double and she did fine with my sister and I (24 month age gap) but she never went out for walks on her own or anything and I need to every day, mainly for my sanity!
I can afford it but wouldn't want to waste £1,100 either! Baby carrier is a no go ask have a dodgey back. I'm not sure about a buggy board as I've heard you have to straddle them weirdly when walking.
Any help would be much appreciated!! 