Same retoucher. Always a nice idea to give the pictures for retouch not to different photographers, but to the same retoucher. So you do not depend on the photographer, his terms and personal style. Moreover, the retoucher can give the same unique style to all your pics.
Retouch yourself. Easy
For nowadays, if you do retouch yourself, for a quick and effective result I would personally recommend:
1. Lightroom(free) for colour correction. You can download and use the same presents for all your pics(also for a phone), copy adjustments to all your pictures, adjust colours and light easily
2. Facetune (Facetune 2, little payment, free trial) for defects. Face retouch, extremely easy to use. Also good for smooth out the folds on the clothing, make some details more sharp or smooth, whiten the background etc. After it the mobile photos looks like from professional camera.
3. Preview (free) to understand and play how your photos will look in the instagram feed.
With them you will not need anything else to create the images for social media fast.