So, a few things to bottom out (I LOVE threads like this). Given you had a rescue, most of the puppy things you really missed...so I'll start with basics😁
If you unsure what breed is best for you, the best thing you can do is actually to speak to breeders - all the crap you read online about breeds is so often wrong tbh. People on mumsnet have great views on what dogs suit what people and half the time they're telling people to get dogs they have no business owning. Sometimes they get it right and sometimes the advice is shockingly insane. So the best thing to do is speak to people who know the breed as a whole and haven't just had a 'really nice lab that just sleeps all day.'
Go on the KC website and use Champ Dogs to find breeders near you of breeds you are interested in (it's useful to cross-reference the two websites tbh). Then, speak to the breeder and say you're considering getting a puppy from that breed, you live locally and you'd really welcome some practical advice about the breed because you want to be 100% you are the right fit for that breed. Most breeders are more than willing to speak to potential buyers (they use it as a form of vetting - my mum did this when she was considering getting an English Setter and the breeder really appreciated it). They'll tell you all you need to know. Most breeders have been in the game for YEARS and no one knows the breed like they do.
Then, once you've bottomed out what breed...you need to speak to several breeders of the same breed. No two breeders are the same. There will be 'feelings' you get from some that put you off - and that's okay. It took me three breeders to get one I felt was the right fit for my most recent dog.
Ask the following questions:
- How many bitches do they have - how many litters will each bitch have ( more than two per bitch is, IMO, a big red flag and more than one a year from multiple dogs is a huge red flag because it is SO exhausting to breed a dog that no one has the energy to do it properly more than once a year. And, of course, if they have multiple breeding bitches then chances are they aren't looking after the puppies or the bitches properly.
- How old is the bitch (KC say one year old, I think two - minimum. Particularly for bigger breeds where they aren't even fully physically developed until two years - my golden is 17 months and he is still growing as are his littermates...the idea of them being bred from is, quite frankly, insane.)
- Why did they choose the sire they did (don't be surprised if you can't see the sire. Most breeders don't own the sire these days).
- What are mum AND dads scores (health scores, for Goldens this should be elbows and hips at minimum. Some do eyes and hearts to - ideally this should be done. Different tests for different breeds - a quick google will tell you what you need).
- Inbreeding coefficient of both parents (KC website will tell you breed average. But don't be wedded to this. My Golden is 10% inbred, which is higher than average, but his hip and elbow scores are incredible).
Then you'll need to decide which breeder you think ticks the most boxes for you and you feel comfortable buying from.
When you go to view a litter:
- Ask to see evidence of the health tests (a good breeder will proactive show you)
- Ask to see all the puppies (if they say no, then run).
- How are they socialising the puppies (hoover, people, different types of surface such as grass, concrete etc)
- Will there be a contract of sale? Can you see the family tree (this isn't hugely important, but its good to be sure the breeder has been careful to avoid breeding from similar lines)
- Will puppies be wormed and vaccinated
- Will the puppy be microchipped
- Can you meet the puppy several times
- Will you pick the puppy or will you be matched
If you do view a litter and something doesn't feel right...don't be afraid to walk away. I have done. It's no bad thing. You have to be SURE you are buying a dog from a good home and that it's been loved and cared for. KC does not necessarily mean it's a healthy or well tempered dog (look at what they've done to French Bulldogs...)
On separation anxiety...it's a tricky one. Goldens in particular are clingy bastards. But it is all about training. I start from day one with all my dogs. For example, I leave the room for ten seconds or so whilst they're playing and half the time they don't even notice. If they do and then cry, I don't go back until they've stopped - otherwise you reinforce that crying = mummy/daddy comes running. Other people don't start doing this until their puppy is 6-7 months old. It's completely personal preference.
On leaving the puppy - you definitely cannot leave a puppy for 3-4 hours until it's at least six months old IMO (and I'm fairly old school in the sense of 'better sooner than later for them to get used to being left). This is for several reasons, but mostly for puppies safety - even in a crate they can cause serious harm to themselves (chewing bars of the crate and getting trapped with their jaws around the bars). After six months, it's a game of chance based on how mature your puppy is. I could leave my Golden for a few hours at that age, but that was mostly because I had two older dogs who were with him and I trusted them to keep him out of trouble...
On socialisation - you can do this from day one. Even before vaccines. You just cannot let other dogs near your puppy OR put them on the ground. But you can carry them in a sling etc (please don't carry them in your arms as they are wiggly little twits and chances are you will drop them). It's a really good idea to socialise them in your arms. Let them sit in your arms outside a cafe or walk along the seafront with you or down to the local shop. This also helps to tire them out (and before you can walk them you will really want to do this). Also take them in the car etc.
On wider training - this starts from day one as well. Even little things like getting them to eat out of your hand (do this carefully, Goldens and labs in particular eat FAST which, if done out of hand, can cause choking if you're not careful) so they associate you with food. Teach them sit/down/stay/recall in the house. Training is a great way to exhaust them as well (and those few weeks before they can go outside are bloody awful tbh). Please do not rely on dog training schools as so many of them are really quite useless and barely teach you anything of actual value.
On bear traps - do not let people approach your puppy when it's still very young (pre and post vaccine) otherwise you'll end up with a dog that associates people with excitement/fusses and then training it out of the dog is a bloody nightmare (particularly if you get something like a Golden which everyone seems to want to pat). When you do let your dog greet other people and dogs, it should be a quick interaction then move on (use food if you need to) - you want them to understand that, yes other people are interesting but you're more interesting!
On the breeds you've suggested. They are all lovely breeds. But yes, I would be wary of rehoming a rescue (Greyhound or Whippet) if you have young children who come around a lot and a neighbouring cat - dogs can be escape artists. My cocker spaniel has jumped a five foot fence before. I'd also be wary on adoption as many shelters are really poor at vetting both the home and the dogs they're trying to get adopted - they either deliberately lie (say a dog isn't reactive, for example, when it is) or they just don't know. Breed specific rescues are better.
Good luck!
Edit: and, of course, it goes without saying that I'm sorry for your loss!