I got my dog about 5 months ago from the SPCA. She's now a year old (plus a month), we got her at 8 months. She was picked up as a stray and I'm unsure how long she had been in her original home to begin with. She went poop outside, but she had bad problems with submissive and excited peeing that it's hard to tell if she was ever fully trained to bathroom outside. What I do know is that when we got her she barely understood sit (only with food in my hand, so I'm half betting this was a natural reaction than actual training), and that was the extent of her tricks.

With only reinforcement of her existing behaviours we've got her to learn: sit, spin, lay, roll (over), pretty (where they sit with their ass on the floor but upright with her front paws off the floor, my mother-in-law's dog helped greatly with teaching by example), tall (where she stands by herself on her back legs) dance (she'll do a 360 while on her back legs) and speak. [Ed: I forgot, we taught her to 'stand', IE move from lay down to sit, or sit to on all fours, because she'd continuously lay when told to sit.] These are all performed easily with verbal command only.

So far we've only trained using single syllable words (dogs don't understand the actual words, their brains are merely receiving a signal and performing an associated action) to keep the input the same. My wife is Canadian and I'm British, so how we pronounce things can be very different sometimes, but a syllable is nearly universal in the Anglosphere... basically we're making our dog multi-region compatible as just in the people she meets there's easily 4 or more dialects that can be giving her commands.

Potential tricks we can teach based off her existing behaviour are: Play dead, jump, growl and as she's got hound in her I'm hoping to one day get a howl command trained. We've noticed hints of 'paw'. She already knows fetch with a thrown object, so it would only be a matter of association training to get her to actually bring things (although for my in-laws their dog just brought the paper when my father-in-law jokingly told the dog to bring it without it being previously trained and their dog was picked up at 8-weeks so I doubt it had previously been trained).

My dog is a Dachshund and Jack Russell Terrier cross and certainly isn't the easiest dog to train, but simple operant conditioning is working great. By making her wait before she's allowed to eat she's actually stopped scavenging when we take her for walks (try ripping a piece of KFC out of a dogs throat, she never bit at me but it's damn hard trying to pry a dogs jaws open and stick fingers down its mouth to stop it choking on a piece of meat with bone in it), she's also stopped stealing food off of the coffee table (she got in from her walk one day and stole a large day old pizza crust off the table and had eaten 4/5ths of it before I finally managed to catch her).

By the best estimates, I have another 14 years with this dog and so far I've mostly been working at removing bad behaviours she had learnt. For all the time I taught tricks, I spent easily twice as long making bad behaviours go extinct. I don't intend to stop training my dog because the more time I spend training her, the more relaxed she is at home (Jack Russell and relaxed are commonly considered antonyms).

I'll have to record it sometime, but the thing I don't think people understand about dogs is that they're consciously trying to comprehend you. When teaching her to sit pretty by verbal command only she would hit this point where she hits the 'zone' her eyes become locked and you can see the gears crunching and then she performed the trick with no signalling. She also tried brute-forcing her tricks; literally she'll perform every trick she's learnt and then give up and start doing 'speak' to every command. You go back 5 minutes later and she'll hit the 'zone'.