second dog. great idea or worst idea ever??

Lindsey • IVF miracle born 12/11/2018, surprise baby #2 due August 2021!
We currently have an 11 lb female terrier who is very well behaved, but VERY needy for attention. When we bring her to places where there are other dogs, she always finds a buddy and could play for hours. Every once in a while, we get to thinking how great it would be to have a second dog, but then we go through all the possible pros and cons and end up talking ourselves out of it. My major concerns are that two dogs become harder to find someone to watch them for vacations, it would double the vet bills, and what if instead of the dogs occupying each other, we just end up with TWO dogs constantly needing attention?!  Thoughts???