Skip to main contentSkip to navigationSkip to footer

Detailed Estimates and Bid Packages

10 min
3/6

Key Takeaways

  • Convert SOW items into quantity × unit cost line items.
  • Bid packages produce comparable contractor proposals.
  • Line-by-line comparison catches scope omissions.
  • Weight price at 40% with other criteria.

Converting preliminary estimates into detailed line-item budgets and professional bid packages.

1

Building the Detailed Estimate

For each SOW item: measure quantity, research unit cost, calculate extended cost, assign to category. Add general conditions, permits, and PM costs.

2

Bid Package Preparation

Include: invitation letter, SOW, plans, bid form template, contract terms, site access instructions. Send to 3-5 contractors with 1-2 week response period.

3

Bid Comparison and Selection

Create line-by-line comparison matrix. Flag items deviating 20%+. Weight: Price 40%, Scope 20%, Schedule 15%, References 15%, Terms 10%.

CriterionWeight
Price40%
Scope Understanding20%
Schedule15%
References15%
Terms10%

Selection scoring matrix

Guided Practice: Bid Selection for $75K Renovation

Selecting a GC from three bids.

  1. 1Bids: A $71.5K, B $78.2K, C $68.9K.
  2. 2C omits $4.2K electrical. Adjusted C = $73.1K.
  3. 3References: A strong, C mixed.
  4. 4Select A—best price/quality combination.

Key Takeaways

  • Convert SOW items into quantity × unit cost line items.
  • Bid packages produce comparable contractor proposals.
  • Line-by-line comparison catches scope omissions.
  • Weight price at 40% with other criteria.

Common Mistakes to Avoid

Selecting the lowest bid without verifying scope completeness

Consequence: Lowest bid omits $4,000-$10,000 in scope items that become change orders at premium pricing

Correction: Perform line-by-line comparison to identify scope gaps before awarding contract

Using the contractors own contract template without review

Consequence: Contract may lack essential protections: retainage, change order process, warranty, dispute resolution

Correction: Use investor-favorable templates (AIA A101 or custom) reviewed by construction attorney

Test Your Knowledge

1.How many contractors should receive a bid package?

2.What weighting should price receive in contractor selection?

3.At what deviation should line items be flagged in bid comparison?