How do you build a bottom-up business plan?

Hi all,

I had a couple of interviews where the interviewers asked if I had experience building a bottom-up and detailed business plan. For example, someone from a BB industrials team mentioned that it is important to break down each line item. Take COGS, for instance. He said you would need to list all the components such as raw materials, freight costs, direct labor, and so on. Then, for each raw material like iron or aluminum, you can use market indexes to forecast the pricing. When it comes to operating expenses, salaries are often split between white-collar and blue-collar employees. You would then forecast the number of employees in each group and apply expected salary increases. (p.s. I answered that one can observe the trend of this cost item's % of revenue. Obviously, the interviewer didn't like this too simple method.)

He was not alone. I also spoke with a few BB TMT bankers who asked about my experience with building bottom-up business plans. I understand that in SaaS, key drivers such as ARR, retention, upsell, and new customer acquisition are crucial to forecasting. However, I work at a full-service bank in the M&A team, and I have never had to build a business plan from scratch. All of our clients provided their own. I had assumed that BBs typically work with more mature companies rather than first-time sellers, and that those clients would already have business plans in place. Also, on the buy-side, it seems difficult to obtain detailed enough data to construct a fully bottom-up business plan? 

That said, I do not have much experience as an analyst yet. I would really appreciate it if you could share your experiences. How often and under what circumstances do you build a detailed bottom-up business plan? How granular do you usually go? Do you break down every income statement item? What about the balance sheet or cash flow statement lines? And what are some typical methods or approaches you use in this process? How do you typically answer this kind of question in an interview?

Many thanks in advance!

4 Comments
 

Building a bottom-up business plan is a highly detailed and granular process, often required in investment banking, private equity, or corporate finance roles, especially when working with companies that lack robust financial models or when conducting due diligence. Here's a breakdown of how to approach it, based on the most helpful WSO content:

1. Key Components of a Bottom-Up Business Plan

  • Revenue Forecasting: Start by identifying the key drivers of revenue. For example:
    • In SaaS, focus on metrics like ARR (Annual Recurring Revenue), retention rates, upsell potential, and new customer acquisition.
    • For industrials, break down revenue by product line, geography, or customer segment, and use historical data or market trends to project growth.
  • COGS (Cost of Goods Sold): Decompose COGS into its components:
    • Raw materials: Use market indexes (e.g., for commodities like iron or aluminum) to forecast pricing.
    • Freight costs, direct labor, and other variable costs: Forecast based on historical trends or industry benchmarks.
  • Operating Expenses: Split into categories like:
    • Salaries: Separate white-collar and blue-collar employees, forecast headcount growth, and apply expected salary increases.
    • Marketing, R&D, and other fixed/variable costs: Use historical percentages of revenue or specific growth assumptions.

2. Granularity

  • Income Statement: Break down every line item to its drivers. For example:
    • Revenue: Units sold × Average Selling Price (ASP).
    • COGS: Raw material costs + labor costs + overhead.
    • Operating Expenses: Salaries, marketing, R&D, etc.
  • Balance Sheet: Focus on working capital items like inventory, accounts receivable, and accounts payable. Forecast these based on days outstanding or turnover ratios.
  • Cash Flow Statement: Link to the income statement and balance sheet. For example:
    • Net income flows into cash from operations.
    • Capital expenditures (CapEx) and changes in working capital impact cash flow.

3. Typical Methods and Approaches

  • Historical Trends: Use historical data to identify patterns and project future performance.
  • Market Benchmarks: Compare with industry averages or competitors for validation.
  • Driver-Based Modeling: Build the model around key business drivers (e.g., customer acquisition cost, churn rate, or production efficiency).
  • Scenario Analysis: Create multiple scenarios (e.g., base, upside, downside) to account for uncertainties.

4. When and Why You Build a Bottom-Up Plan

  • Circumstances:
    • When working with startups or first-time sellers who lack detailed financial models.
    • During due diligence for M&A transactions, especially on the buy-side.
    • For internal strategic planning or when evaluating new business lines.
  • Frequency: It depends on the deal type and client sophistication. Mature companies often provide their own plans, but less mature or smaller firms may require you to build one.

5. How to Answer in an Interview

  • Show Understanding of Granularity: Emphasize your ability to break down each line item and identify key drivers.
  • Highlight Analytical Skills: Mention your experience with driver-based modeling, market research, and scenario analysis.
  • Acknowledge Limitations: If you lack direct experience, explain how you would approach the task logically and reference any related experience (e.g., building financial models or analyzing client-provided plans).
  • Tailor to Industry: Demonstrate knowledge of industry-specific drivers (e.g., ARR for SaaS, raw material costs for industrials).

Example Response

"In my current role, I haven't built a bottom-up business plan from scratch, as our clients typically provide their own. However, I understand the process involves breaking down each line item into its components. For example, in forecasting COGS, I would analyze raw material costs using market indexes, freight costs, and direct labor. For operating expenses, I would separate white-collar and blue-collar salaries, forecast headcount, and apply expected salary increases. While I haven't done this end-to-end, I have experience analyzing and refining client-provided models, and I would approach this task by leveraging historical data, market benchmarks, and driver-based modeling."

By demonstrating your understanding of the process and your ability to think critically, you'll show interviewers that you're capable of handling this task, even if you haven't done it before.

Sources: 21 Finance Interview Questions and Answers, 21 Finance Interview Questions and Answers, Investment Banking Interview Questions - 15 Answers to Land the Job, How would you approach a 4 hour case study?, Investment Banking Interview Questions - 15 Answers to Land the Job

I'm an AI bot trained on the most helpful WSO content across 17+ years.
 
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Depends on the type of deal. 

I have worked with a company weeks away from bankruptcy so we had to get super granular with AP and AR and timing of inventory orders. Totally sucks to do but had to do it. If a company is in normal operation situation, just assumed a % of COGS or whatever as working capital needs to blanket pre-fund that account. We looked at each contract the company had (~25 contracts) and modeled out the revenue timing terms, had detailed inventory order and payments linked to production (~8 major inventory components ordered and paid for on different terms), G&A was projected by actual headcount, etc. All super detailed monthly basis.

Normally just add $Xmm at close for working capital and call it a day, run G&A proportional to sales / unit growth to a point (# of employees will scale roughly with revenue, more so for blue collar vs white collar however). This is basically all I do, and grow costs with inflation. If a commodity with a futures market is a significant driver, easy enough to pull in the futures data and just use that for the volume of commodity you need.

You need to be careful with super detailed forecasts for longer than a year, they are basically useless past that point so just be conservative with the mechanics of the projections if building a longer term model, no need to over complicate it. Just remember, the financial model should not be more complicated than the business- a simple business needs a simple financial model where a complicated business will need a complicated financial model.

 

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