cost-estimation-resource

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---
name: "cost-estimation-resource"
description: "Calculate construction costs using resource-based method. Estimate project costs from work items, physical resource norms, and current prices."
homepage: "https://datadrivenconstruction.io"
metadata: {"openclaw":{"emoji":"🧮","os":["darwin","linux","win32"],"homepage":"https://datadrivenconstruction.io","requires":{"bins":["python3"]}}}
---

# Cost Estimation - Resource Method

## Business Case

### Problem Statement
Traditional costing challenges:
- Fixed unit prices become outdated
- No visibility into cost components
- Difficult to adjust for conditions
- Limited cost analysis capability

### Solution
Resource-based costing separates physical resource consumption (norms) from prices, enabling accurate, adjustable, and transparent cost estimation.

## Technical Implementation

```python
import pandas as pd
from typing import Dict, Any, List, Optional
from dataclasses import dataclass, field
from enum import Enum


class ResourceType(Enum):
    LABOR = "labor"
    MATERIAL = "material"
    EQUIPMENT = "equipment"
    SUBCONTRACTOR = "subcontractor"


@dataclass
class Resource:
    code: str
    name: str
    resource_type: ResourceType
    unit: str
    unit_price: float
    currency: str = "USD"


@dataclass
class ResourceNorm:
    resource_code: str
    consumption: float  # Units per work item unit
    waste_factor: float = 1.0  # 1.1 = 10% waste


@dataclass
class WorkItem:
    code: str
    name: str
    unit: str
    resources: List[ResourceNorm] = field(default_factory=list)


@dataclass
class CostLineItem:
    work_item_code: str
    work_item_name: str
    quantity: float
    unit: str
    labor_cost: float
    material_cost: float
    equipment_cost: float
    subcontractor_cost: float
    total_cost: float


class ResourceBasedEstimator:
    """Calculate costs using resource-based method."""

    def __init__(self):
        self.resources: Dict[str, Resource] = {}
        self.work_items: Dict[str, WorkItem] = {}
        self.overhead_rate: float = 0.15
        self.profit_rate: float = 0.10

    def add_resource(self, resource: Resource):
        """Add resource to database."""
        self.resources[resource.code] = resource

    def add_work_item(self, work_item: WorkItem):
        """Add work item with resource norms."""
        self.work_items[work_item.code] = work_item

    def load_resources_from_df(self, df: pd.DataFrame):
        """Load resources from DataFrame."""

        for _, row in df.iterrows():
            resource = Resource(
                code=row['code'],
                name=row['name'],
                resource_type=ResourceType(row['type'].lower()),
                unit=row['unit'],
                unit_price=float(row['unit_price']),
                currency=row.get('currency', 'USD')
            )
            self.add_resource(resource)

    def load_work_items_from_df(self, items_df: pd.DataFrame, norms_df: pd.DataFrame):
        """Load work items and norms from DataFrames."""

        # Group norms by work item
        norms_grouped = norms_df.groupby('work_item_code')

        for _, row in items_df.iterrows():
            code = row['code']
            resources = []

            if code in norms_grouped.groups:
                item_norms = norms_grouped.get_group(code)
                for _, norm_row in item_norms.iterrows():
                    resources.append(ResourceNorm(
                        resource_code=norm_row['resource_code'],
                        consumption=float(norm_row['consumption']),
                        waste_factor=float(norm_row.get('waste_factor', 1.0))
                    ))

            work_item = WorkItem(
                code=code,
                name=row['name'],
                unit=row['unit'],
                resources=resources
            )
            self.add_work_item(work_item)

    def calculate_work_item_cost(self, work_item_code: str, quantity: float) -> CostLineItem:
        """Cal