Half my closet has the clothes I used to wear (twice before) and am working my way down to again, including enough tuff in the middle to tide me over. Have done this dance several times and while I swear each time I'll keep it off, I don't - that's just the way it is. So rather than spend and lose a fortune in clothes every time, I just keep the good, classic styles and I always have something. Gives me great pleasure to find something in my closet that fits again, rather than having to go out and pay some inflated price for something new. I've been fat for so long this time that all my old stuff is new again anyway
For work - try Chico's Treveler line - always looks great, very professional, no wrinkle and elastic waistbands that work as well as you are losing weight as they do when you are gaining. And since the styles are not skinny tight, they never look baggy.