Building time
My experience is a little different than most. I was a career changer. I had flown for pleasure for about five years before I decided to make the switch. I had worked on ratings all during the time, but my work hours were not conducive to proper training. So, I had a lot more time than most newbies - about 950 total and about 35 multi when I starting to apply to places. I was hired in my first full-time job, instructing at ERAU at about 1300 total but still only 49 of multi. I paid for all of the multi, for training and for shooting approaches - that B55 Baron was fun!!
I built hours quickly after I started working, but in singles at first. I had 1500 hours about three months later. Six months later, I got into the multis. A year after I started at Riddle I had about 2250 total and about 300 of multi.
The multi time still wasn't enough for most commuters, though. Back then, they wanted 500 of multi. As you can see at the left, I eventually got that. I started to be called with maybe 600 or so of multi. Don't forget, that was the early '90s. A lot of commuters these days only want 200 of multi - though I'd bet competitive times are more like 500+.
Hope that helps. Of course, the more flying you can do, the quicker you'll build experience.