Time. It's almost 24/7 if you get a puppy. MayB go to a boarding kennels in your area and offer up your time for 3 months. That way you will meet lots of dogs, owners with experienced kennel staff.
Vets Bills can be HUGE! as well as a drain on emotions. Pedigree dogs have more health problems than 1st cross or mongrels.
Cinnamon Trust is always looking for fosterers - when people to into hospital in a hurry or when they need care when going away on Holliday. Or when a new baby arrives and they need to spend time getting into a routine: true for new parents as well as grandparents.
I grew up with working labs and jack Russell terriers. Most breeds are split from working strain to 'pets' even border collies. However, hunting and chasing remains in most breeds so be prepared for time spent waiting for them to return ;-). I spent many a happy hour watching mine following their noses, enjoying the sniffs .
My cocker spaniel was born in 1988 and or show type, she had enough brain to enjoy putting up mice and digging for moles. How are U with picking up soft poo? Firm is hard work but an early morning splatter

. I cared for a King Charles, two cockers and a retriever for various owners in the locality. Meant no bills and they went home at night. ;-)
MayB meet up with other dog walkers in your area?
If U do get a dog; and if U decide to go on holiday without it, do book kennels at least 6 months in advance because in some areas, they get full very quickly. Any decent kennel establishment will allow visitors during working hours to fetch up and look round. Any that a 'not now' attitude are to be avoided. Also, no boarding kennel should smell.
Do U have lots of good safe walking areas, i.e. public footpaths, beside lakes etc.? For the dog which was deaf I had a pony leading rein so that he felt free but couldn't run far.
1 reason that we don't have pets is that we enjoy a deep sleep well into the morning, whereas

have a habit of waking at dawn

. My cat would lift my eyelids in the early hours when he wanted feeding - purring gently as he sat on my chest.