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Part 6 of 7 · Background check chaser series ~5 min read

What the background check chaser costs

Hiring volume in a small business is low and the model barely features: this system is almost entirely email and a scheduled sweep. Twelve checks a month is roughly three starters. Here is where each cent goes.

Key takeaways

  • About $1 a month at 40 checks. Roughly $2 at 150 checks.
  • One Bedrock read per check is the only line that scales. Everything else is rounding.
  • Nothing is always-on, so a quiet month genuinely costs almost nothing.
  • Messaging is the largest variable line here, because chasing is the whole product — and email at this volume is still fractions of a cent.
  • The duplicate test runs before the read, so resends are free.
  • The three real risks: a retry loop, storage nobody expires, and a bigger model than the job needs.

The bill at three volumes

These are US East prices at the time of writing, at three volumes that bracket most small businesses. Find the bar closest to your own and read across.

Monthly cost of the background check chaser at three volumesA stacked bar chart with three bars, one per volume tier: 12 checks totalling about $1, 40 checks totalling about $1, and 150 checks totalling about $2. Each bar is stacked from bands. The largest and fastest-growing is Bedrock, one read per check, in teal. Then SES for the messages, in pink. Then S3 and DynamoDB storage in green. Then a fixed orange band for Secrets Manager and AWS Budgets, which is eighty-six cents at every volume. Then a grey band for Lambda, SQS and CloudWatch. A note says the read is the only bar that grows with the business and the orange band never moves.$0$1$2$3$4~$1.2812 checks~$1.3740 checks~$1.73150 checksBedrock — one read per checkSES — asks, results, receiptsS3 + DynamoDBFixed — Secrets Manager, BudgetsLambda, SQS, CloudWatchThe read is the only bar that grows with the business. The orange fixed band never moves.
Fig 1. The monthly bill at three volumes. The teal band — one model read per check — is the only part that grows; the orange fixed band is the same 86 cents at every volume.

Line by line

LineAt 40 checksHow it scales
Bedrock read$0.06Linear. One call per check, roughly 1,800 in and 200 out tokens.
SES$0.03Linear. About 3.4 messages per check.
DynamoDB + S3$0.29Storage grows with what you retain, not with throughput.
Lambda + SQS$0.12Linear, and effectively free at this scale.
CloudWatch$0.16Flat, if you set retention. Unbounded if you do not.
Secrets Manager$0.40Flat. One secret, $0.40 a month.
AWS Budgets$0.46Flat. Two actions, so you find out before the bill does.

The model is barely used here — only to match an inbound reply to an outstanding item where the thread headers do not settle it. Most updates cost nothing at all.

The three ways this bill surprises you

Every one of these has happened to somebody, and all three are cheap to prevent.

  • Storing what you relayed. The privacy design depends on the copy being deleted after forwarding. A bucket that quietly retains reference PDFs turns a status tracker into a system with a retention policy and a legal basis to document.
  • Chasing on a fixed cadence rather than the owner’s. Emailing an agency every two days against a fourteen-day turnaround is noise that gets you filtered, and being filtered by a screening agency is genuinely expensive.
  • Log retention left at never. This system does very little most days and will otherwise be almost entirely a CloudWatch bill within a year.

What it costs when nothing happens

This matters more than the headline number for a seasonal business. In a month with nothing to process the bill is the fixed band: Secrets Manager at forty cents, AWS Budgets at forty-six, and a few cents of storage. Call it a dollar. There is no instance to stop and nothing to remember to turn off.

The monthly bill at four volumes plus one failure modeA horizontal row of five boxes. Quiet month, about one dollar. 12 checks, about $1. 40 checks, about $1. 150 checks, about $2. And one bad retry loop, about two hundred dollars. A note says four of these are the design working and the fifth is a missing dead-letter queue.THE BILL, AT A GLANCEQuiet month~$112 checks~$140 checks~$1150 checks~$2One bad loop~$200Four of these are the design working. The fifth is a missing dead-letter queue.
Fig 2. The bill at a glance, including the one that is not a volume at all. A retry loop with no dead-letter queue costs more than every legitimate use of the system put together.
  • Management
  • Analytics
  • Front-end & mobile

Set these on day one

  • A dead-letter queue on every SQS queue, with a maximum receive count of three.
  • Thirty-day retention on every CloudWatch log group. There is no default that is safe.
  • An S3 lifecycle rule on the object prefix, tiering at 90 days and expiring at your actual record-keeping horizon.
  • Two AWS Budgets actions — one that emails at half your expected spend, one at double it. The second is how you find out about a loop in an hour instead of a month.
  • Provisioned concurrency: none. Nothing here is latency-sensitive enough to justify paying for a warm function.

Next: the same system drawn for engineers — service names, resource identifiers, IAM scopes, table schemas and the model id.

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