Does your shed have electric, plumbing, a/c?

The issue is the plumbing running from the center floor connecting to the old bathtub.

Anything with major work like kitchens , baths, structural, electrical, plumbing, etc will likely roll into more time...Where did you get the 3-4 months timeline?

. $45k from several unexpected large repairs (water leaks, roof collapse, siding rot, plumbing main line, etc.)These issues are also causing me to rethink the assumptions in my model, increasing my vacancy rate from 8% to 12%, repairs from 5% to 20%, and capex from 5% to 20%.

Renovations would cost around $30,000 but the only things I've done are Plumbing, foundation work, gas line, and new windows.

You can then approach a plumbing company to negotiate special rates for those involved.

Renovations would cost around $30,000 but the only things I've done are Plumbing, foundation work, gas line, and new windows.

The house will need new interior everything - plumbing, electrical, kitchen, bathroom, walls, etc. 

Tenant also agrees to the following:-All drains, waste pipes, and plumbing are accepted as clear by Tenant at the time of occupancy, and any material blocking them after occupancy shall be repaired at Landlord’s cost, unless determined by repair person that such blockage occurred during the time Tenant controlled the Premises and due to some fault or negligence of Tenant, specifically excluding blockages caused by roots or backups from the street.

The plumbing?