Hey!
I didn't get a double buggy and never regretted it
My age gap was 2y, my son hated going in the buggy anyway, and we had a mountain buggy which works v well with buggy board and is strong enough to sit 2 year old on top or on the foot rest at front....
He was on a scooter soon enough, and the last thing I needed was a heavy, double buggy
Just thought I would put in a vote for single buggy ++