Estimated cost of replacing rotted joists

[Samantha Klein]

Hey all, I looked at a duplex recently where the floors in back section had sunk approx 4-6" and pulled the wall with it in some spots, looks to be sinking towards the middle of the back section. Some of the joists have rot and are weak, the problem is there is only around 12-14" under the house, no crawlspace, they actually had a hole cut in the floor in a closet for access. How difficult is it and how expensive to replace the joists, I would assume they should probably all be replaced, approx 20 of them, would the whole floor need to be removed to work from on top or do you think 12-14" is enough space for someone to work from the bottom? The duplex currently has tenants.