Thank you all for giving me the valuable information.

I think the best way out would be get the job done outside, instead of
1. Use free software, with limitation, lot of learning time,
2. Invest in good software, again a lot of learning time, hire a draftsman to do it...pass on the information to him...how much he visualizes,etc,etc,etc..

A better way out will be to get this job done outside.

Anyways, Thank you all for the information.