I have around 200 pages for which I need only meta description to be written in 160 characters. or around 20 words. Pm me your offer
You do realize that Google isn't giving much (if any) weight to Meta tags anymore, right? See here before you spend your money on something obsolete: http://www.mattcutts.com/blog/keywords-meta-tag-in-web-search/
Google isn't the ONLY search engine that's relevant for traffic. And while they may not value them as being important, Yahoo and Bing do. I'm pretty sure that the OP is aware of this, and realizes that they can be just as good of a traffic source as Google. Some people aren't reliant on just Google for their traffic, and I'm betting that the OP is one of those people. To the OP, if you still need someone to write these up for you, then go ahead and send me a PM with the details. I'll only charge you $1.00 for each page, and I'll make sure to optimize them so that they pack the most PUNCH!
FYI Yahoo stopped "supporting" Meta Keyword tag back in 2009 Yahoo states: I'm sure the same is true for bing. So, in my opinion, you would be much better off paying someone for some on/off page optimization than paying them to do meta tags.