I have worked in fashion industry for 4-5 years. And I work closely with pattern maker as well as Seamtress. I have read and produce tech packs for bulk production, which exports to USA and UK.
I can produce pattern and sew, which helps me to easily produce techpacks. But since I am not in your country, I did not have the samples in hand, producing tech packs via photos/ illustration might have its own limits. I suggest that can only provide tech packs on sewing techniques, types of finishing but not on measurements and size grades. Because measurement tech packs requires real sample measuring and fitting.
Bid for 4 designs. Each tech pack in pdf, 3-12 pages each, depends on designs. Size grading not included. Will not take money if you feel that tech pack are not clear enough for production. Only charge on designs that are processed to productions.