Floor Plan Calculator
Find out what every day on the lot really costs. Enter your inventory, average unit cost, rate, fees and days-to-sell to see carry cost per unit, monthly interest and when curtailments start biting.
Independent floor plans typically run 9-13%
Floor / draw fee charged on each unit
First curtailment due at
Carry cost per unit as it ages
Amber = past your first curtailment, when a principal paydown is also due.
Carry cost per unit
$319
1.8% of unit cost · $5.42/day in interest
Your average unit sells before its day-60 curtailment - no principal paydown on a typical unit.
Compare floor plan offersEstimates for illustration only - not a loan offer or commitment. Actual rates, terms and fees depend on the lender, your credit and financials, and the specific deal.
How floor plan interest is calculated
Most floor plans charge simple interest every day on the outstanding balance of each unit: unit cost × APR ÷ 365 × days floored. An $18,000 unit at 11% costs about $5.42 a day, or roughly $244 if it sells in 45 days.
On top of interest, lenders charge per-unit fees - usually a floor (draw) fee on each unit, sometimes audit, extension or late fees. The calculator adds your per-unit fee to the interest so you see the full carry cost, not just the rate.
Why days-to-sell matters more than the rate
Dealers shop floor plans on rate, but time on the lot moves your cost far more. On an $18,000 unit at 11%, interest alone grows like this:
| Days on floor plan | Interest ($18K unit @ 11%) | What it means |
|---|---|---|
| 30 days | ~$163 | Healthy - a rounding error in your gross |
| 60 days | ~$325 | Manageable - first curtailment usually lands here |
| 90 days | ~$488 | Margin pressure - plus a second curtailment |
| 120 days | ~$651 | The unit is eating its own profit |
Turn beats rate
At 45 days, the gap between a 9% and a 13% floor plan is about $89 per unit. Letting the same unit sit 90 days instead of 45 adds about $244. Cutting days-to-sell is the cheapest rate cut you'll ever get.
Curtailments: the cash you need on day 60
A curtailment is a mandatory principal paydown on a floored unit, triggered a set number of days after you draw - commonly 10% at 60 days, then more every 30 days after. It isn't a fee, but it is cash out the door on a car you haven't sold.
Set your first curtailment day and percentage above: if your average unit sells after that day, the calculator shows how much cash each aged unit will need. Plan that money before it's due, not when the notice arrives.
Sizing your floor plan line
- Start from the inventory you want to carry, not the line you're offered: units × average cost ≈ the line you need.
- Add 15-25% headroom for auction runs and seasonal peaks, so a good week at the lanes doesn't max you out.
- Watch your aging report - units past 90 days tie up line capacity and push curtailment cash.
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Common questions
The calculator gives you the shape of the deal. A specialist can show you real offers for your exact numbers.
Apply NowIndependent-friendly floor plans typically run about 9-13% APR, usually priced as a spread over prime, plus per-unit fees. Strong, high-volume dealers land at the low end; newer lots and thinner files price higher.
Multiply the unit's floored balance by the APR and divide by 365. At $18,000 and 11%, that's about $5.42 a day - multiply by the days the unit sits to get its interest cost.
Common ones are per-unit floor (draw) fees, curtailment or extension fees, audit fees, and late or reinstatement fees. Ask for the full fee schedule in writing - fees can add up faster than a point of interest.
Roughly your target inventory count times your average unit cost, plus headroom for auction runs. Twenty units at $18,000 is about a $360K line. Lines commonly run from $50K for newer lots to $10M for high-volume dealers.
No - it's an estimate to help you compare structures. Your actual rate, fees and curtailment schedule depend on the lender, your history and the inventory you floor.