Active job

Soft spot in the floor under the carpet - subfloor need to be replaced

There is a soft spot in the floor under the carpet, the subfloor has likely been weakened or damaged or rotten. We would like to have a quotation for all the necessary jobs which is not shown well in the photo - we have a video but cannot upload here. We don't have any expect cost as we are not sure how much work needed but would like hear the reasonable and honest quotation.