Do you train on COCO?

I did not use the COCO dataset. I used my own dataset which consists of 5 classes with 400 images each.

Than the answer depends on your data I would say

Understood, I'll try to add more dataset. Thanks!!

May I also ask, if is it possible to get a 90% average precision? or mean average precision on the SSD mobilenet?

Depends on the dataset. If you would like to detect blue rectangles on a white background you could even achieve 100%.

Thanks for the answer really appreciated it!!