Rewards are a great idea! I like cloths as a rewards idea. Since hopefully I'll be shrinking out of mine.
Since I regained weight recently my inital reward will be that I'll be able to wear some awesome jeans I bought shortly before I put on weight. I'm not gonna plan rewards between 183 and 170, I have cloths in plenty at this spectrum since its been my weight for awhile. (until recently) Besides those jeans are like new. I'm guessing they will fit at around 170, so thats the first.
170 lbs- Jeans already in closet! (also my fitted shirts that have been relagated to the back of the closet cause they hug my recently expanded muffin top)
165 lbs- A summery dress (if its still warm enough

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160 lbs- New running pants (I fell and tore a hole in the knee of mine

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155 lbs- A whole new cute outfit, whatever tickles my fancy because this is goal!!!