Facebook ads for a Bemidji plumber don't behave like Facebook ads for an LA marketing course. Different math, different audiences, different timelines. So before you set a budget or judge the campaign, you need to know which number actually tells you whether the ads are working.
Almost every local owner who's ever asked me about Facebook ads is asking the same underlying question: "Will this work for my business, or am I about to set $1,500 on fire?" Fair question. The answer depends on three things very few owners calculate upfront: what you're willing to spend to learn, what a customer is actually worth to you, and whether you're judging the campaign on the right number.
Most small-town service businesses can run profitable Facebook ads. Most of them will not, because they'll quit at week three, judge the ads on the wrong metric, or never measure lifetime value in the first place. Let's walk through the version that actually works.
Budget: the floor before you can learn anything
Meta's algorithm needs data to optimize. Below a certain spend, you're not really running a campaign, you're running an experiment too small to draw conclusions from. For a service business in a Bemidji-sized market, the practical floor is around $30/day, or roughly $900/month. Less than that and the algorithm doesn't get enough conversion events to learn who to show your ads to.
That floor doubles in larger markets like the Twin Cities, Duluth, or Fargo, where competition for impressions is heavier. But in our region, $30-50/day is real money on the table.
The realistic learning window is 60-90 days. The first 30 are setup and signal collection. The next 30 are when the algorithm starts to find your actual customers. Judging Facebook ads by week 2 is like judging a garden by what's visible the day after you plant it.
The gold standard is LTV:CAC. Most owners never calculate it.
LTV:CAC stands for Lifetime Value to Customer Acquisition Cost. It's a ratio. It is, full stop, the only number that tells you whether paid advertising is working as a long-term channel.
Two terms to define before we can use the ratio. CAC — Customer Acquisition Cost — is just total ad spend divided by new customers acquired. Spend $1,500 in a month, get 5 new customers from the ads, your CAC is $300. LTV — Lifetime Value — is the total gross profit a customer is worth to you over the time they remain a customer. Not gross revenue. Gross profit. (More on this in a minute, because it's where most owners get the math wrong.) The ratio is LTV divided by CAC, and the healthy floor is 3:1. If your CAC is $300, you need a customer worth at least $900 in gross profit over their lifetime for the math to make sense.
Below 3:1 you're either breaking even or losing money over time, even if the campaign "looks good" on a leads-per-day basis. Above 3:1, you can scale spend confidently. At 5:1 or above, you should be spending more than you currently are.
Lifetime gross profit, not gross revenue. This is where most people get it wrong.
A roofer doesn't have $14,000 of value sitting in a new customer just because the job was $14,000. Materials and labor and overhead might be $10,000 of that. The actual gross profit is $4,000. That's your real LTV, not the invoice total.
The other side of this is repeat business. A homeowner who gets a new roof isn't likely to need another one for 20 years, but they might also be your gutter guy, your siding guy, and the person who refers two neighbors over the next five years. A plumber's LTV looks different again — the first call is $400, but the same homeowner calls you for the next 15 years, every 2-3 years on average, for everything from a water heater to a sump pump. That's where the real LTV is.
For most local service businesses in our region, when you actually do the math:
- A roofing or one-off-install customer's gross profit LTV is usually $3,000-$8,000.
- A recurring-service customer (HVAC, plumbing, garage door, lawn) is usually $1,500-$4,000 over 5-10 years.
- A premium home-improvement customer (kitchens, baths, custom builds) can be $20,000+.
Once you know your real LTV, you can do the math backwards. If your LTV is $4,000 of gross profit and you want a 3:1 ratio, your CAC can be up to $1,333 and you're still winning. That changes the picture entirely. A lot of owners decide $300 per customer is "too expensive" without realizing that customer is going to print $4,000 of profit over the next decade.
The trap of judging by leads or even closed deals in month one
The failure mode I see most often goes like this. An owner starts Facebook ads, gets 12 leads in the first three weeks, closes 2 of them, looks at the ad spend so far ($1,200), and concludes "I'm paying $600 per customer, this is too expensive." So they shut the campaign off.
What they missed is three things that all compound. First, of the 10 leads who didn't close, 3-4 of them will close inside the next 90 days if they're followed up with properly — so the real CAC drops to $200 once those land. Second, the 2 customers who did close are worth $4,000+ in gross profit each, which makes even a $600 CAC a 6:1 ratio. Third, the algorithm was still learning in those first three weeks. Weeks 4-8 would have been measurably cheaper per lead than weeks 1-3.
If you can't tolerate three months of feeling like the numbers don't quite work, paid social is probably not your channel. That's not a judgment, it's just true. For a lot of local businesses, organic Google traffic plus a tight referral loop is a better fit than paid acquisition, full stop.
Honest expectations for a Bemidji-area service business
A healthy, well-run Facebook campaign for a service business in our region looks like this at the end of month three:
- Spending $1,000-$1,500/month.
- Generating 20-40 leads/month.
- Closing 4-8 of those into paying jobs.
- Real CAC sitting between $150 and $400.
- LTV:CAC ratio in the 4:1 to 8:1 range, depending on industry.
- Most of the ROI showing up in months 4-12, not month 1.
If you're running ads and the numbers look meaningfully different from that range, something is off, either the creative, the targeting, the follow-up, or the LTV calculation. Worth fixing before you walk away from a channel that, for the right business, prints money for years.