There is no such thing as 'no cry' methods.
There is either leave your baby alone to cry methods or sit with your baby while they cry methods. That's the bare fact of the matter. 'The No Cry Sleep Solution' sells brilliantly because that's what everyone wants, but its main success is in getting you to adjust your expectations - you don't get a baby that sleeps 12 unbroken hours per night within a week of implementing its methods.
OP - we used Ann at Nurturing Sleep (she comes up easily if you Google). She is one who doesn't advocate leaving alone to cry and has a very holistic method - she doesn't just focus on sleep but on the whole baby, which is interesting. I used her with DS1 when he was around 19mo (he was sleeping well within about six weeks) then with DS2 when he was 6mo, but with the latter, it didn't work at all until he was almost 18mo. This re-enforced to me that sleep is an entirely developmental skill - neither of mine was ready to sleep independently, or for long unbroken stretches, until they were much older. Co-sleeping was the only solution.
FWIW, I went back to work full time when each was 8mo and waking every 90mins to 2hrs every night. I was absolutely sick with horror about how I was going to cope before I went back, but I had no choice. It actually wasn't that bad. When you have something else to think about other than how little sleep you've had, you can actually plough through the day better than when you're stuck at home with a baby thinking about nothing else other than sleep.
Both sleep fine now, by the way at 5yo and 3yo. They've neither of them ever done the fabled '7-7' because they obviously just don't need as much sleep, but they do reliably do 8pm-6am, self-settling, in their own rooms. It does end, I promise 