When did he start urinating inside?
Did it coincide with having a child? Or with getting your cat?
Like it or not you have a responsibility for his health & wellbeing. You also have a responsibility for your own. Both can be immeasurably improved by making your dog a priority once again and taking steps to correct his behaviour.
Re the urinating indoors - first step is the vets, as it should always be when an animals toileting habits change.
The vet will check for medical issues and advise some basic behavioural training. If no medical cause can be found, and neutering doesn't help, then it's likely to be stress. In which case, the poor thing really does need some care & attention from you.
A baby gate will block him from upstairs in the meantime.
Re. The barking: this sounds like boredom, stress or both.
What breed is he?
How often is he walked?
What attention is he given apart from walks and feeding, is he played with?
He might need more mental stimulation.
There are several things you can do before embarking on the road of hiring behaviourists but they all require some care from you (and presumably your partner).