Need drone photographs stitched together

I have 131 photographs taken from a drone, which followed an automated flight path. Each photograph is 5472x3648 pixels and there is approx 85-90% overlap in each photograph and each photograph was shot and is named in the order they were taken (first image is 0973 - I will explain all this to the freelancer) I need somebody to stitch the photographs together to create one seamless image. Unfortunately due to an error, some of the pictures were shot at different shutter speeds so may need colour/brightness matching. Due to the nature of the building being photographed, automated stitching software is unlikely to be able to do this job - so please only bid if you can do it manually. I need the final result to be one (very very) large, with no visible stitch marks or colour differences. The final image quality must be exceptional - there is no room for error - so please bid accordingly. Please only bid if you have read the brief - I will not respond to generic/send-to-all bids.