It is possible to work full time if you can make alternative arrangements for your pup whilst you work.
I have reduced my hours slightly since getting Alfie, he is now 22 weeks, which means I can work opposite shifts to my OH so Alfie has someone with him all of the time.
There is one day that we both will have to work that will clash, but my mother in law will be looking after him on that one day a week. If you have willing friends or family to take the pup for you whilst you work is an option, as is pet sitting services. Obviously there are costs involved with that.
We had a total of 2 months annual leave booked off between us for when Alfie came home, but my OH developed a bad back, which was perfect timing really.
This means Alfie has had constant attention since 8 weeks old, and I have to say I now wouldnt do it any other way, it has paid dividends to his training etc.
The most time Alfie has been left up till now at 22 weeks is 2 - 2 1/2 hours max. I wouldnt be happy any longer to be honest.
We pay £20 a month insurance, then you have grooming costs, food costs, initial vaccintaions, the list is endless really.
Good luck in whatever you decide, pups are very hard work, but so rewarding if you can commit to them 100%.