Solar ERP vs CRM plus Tally: which setup fits a solar company?
Sheets, a stitched stack of CRM, project tool and accounts software, a configured ERP, or a custom build. Four setups, when each breaks, and a rule for the order to try them in.
- Four setups: sheets plus accounts software, a stitched stack, a configured ERP, a custom build.
- Move up when you can no longer see live project margin or approval delays.
- A stitched stack fails at the joins: quote to project, purchase to project, site to accounts.
- Custom build is last, not first. We sell it and we still say so.
- Fix the process on paper before choosing any tool.
Quick answer
Try the simplest setup that can show you live project margin and approval delays, and move up only when it cannot. Sheets and accounts software work for a few concurrent jobs. A stitched stack of CRM, project tool and accounts software works until double entry and missing project cost data bite. A configured ERP suits most growing EPCs. Custom build is the last option, justified only when your process is unusual and no configurable system fits. Do not buy an ERP to fix a process you cannot describe.
We build custom software, so we gain when companies choose custom. Our advice here is to choose it last.
What are the four setups?
| Setup | Best when | Breaks when | Cost shape |
|---|---|---|---|
| 1. Sheets plus accounts software (such as Tally) | A few concurrent jobs, one person owns the sheet | Several editors, purchases outside the sheet, margin known only at close | Low cash cost, high attention cost |
| 2. Stitched stack: CRM + project tool + accounts software | Sales pipeline matters, projects are moderate | Quote does not become a project budget; purchases and site costs do not reach the project; double entry | Moderate subscriptions, hidden labour at the joins |
| 3. Configured ERP (off-the-shelf or open source) | You have more than a few concurrent projects and a describable process | Your process is unusual, or nobody owns configuration | Licences plus implementation; configuration skill is the real cost |
| 4. Custom build | Process is distinctive and configuration would bend the product out of shape | You cannot define the process, or you will not maintain it | Highest build cost plus ongoing ownership |
What is the rule for moving up?
Move up a level when the current setup cannot answer three questions in under five minutes:
- What is the forecast margin of each live project, and how has it moved since last week?
- Which projects are waiting on an external approval, for how many days and on whom?
- How much is due by milestone this month, and what is blocked?
If the answers take a day of calling and copying, you have outgrown the setup. If you can answer them from what you have, moving up will mostly add cost.
Why do stitched stacks fail?
At the joins. Three are common:
- Quote to project. The quote BOM sits in the CRM or a proposal file, and the project budget is retyped into a sheet. The two drift.
- Purchase to project. Purchases are entered in accounts software against suppliers, not against projects, so project cost is invisible until someone reconstructs it.
- Site to accounts. Labour and expenses reach accounts weeks later as lump sums.
Each join is a manual copy. Every manual copy is a place for the numbers to differ. A stitched stack works when someone is paid to hold the joins together, and it fails when they leave.
What should you do before you choose?
- Describe the process on paper. Lifecycle, handoffs, approvals, documents. If two managers describe it differently, fix that first. A new system will expose the disagreement.
- Write the requirements. Use the checklist.
- Decide the master for each fact. Which system owns customers, projects, costs, invoices, serials? One master each.
- Pilot on one branch or one project type. Not the whole company.
When is custom the right call?
When your process is distinctive enough that a configured system would need heavy bending, and you are ready to own maintenance: updates, hosting, security, a person who understands it. For the general decision, read build custom software or buy SaaS. For most EPCs, a configured system or a careful stitched stack is the right first answer.
Where does this not apply?
If you do utility-scale development with project finance, your needs lean toward asset management and lender reporting, which this page does not cover. This is about rooftop and C&I EPCs.
What to do this week
- Try to answer the three questions above for your live projects. Time yourself.
- Write down where numbers are retyped between tools.
- Name the person who owns the sheet today, and ask what happens when they are away.
Part of the guide Running a solar EPC business on connected systems.
The four setups, the three questions and the join failures are our own reasoning, drawn from how project businesses commonly run, not from measured data. No vendor was compared or tested. Tally is named as a common example of accounting software only.
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