Par levels: never run out again

What a par level is

A par level is a number for each item on your shelf. It is how much you want to have in the cupboard right after a restock, so that you can get through to the next restock without running out.

It is a simple idea, and it fits a short-let well. Without one, restocking runs on memory and panic. The cleaner messages to say the coffee has gone, you make a late trip to the shop, and you pay whatever the corner shop charges. With one, restocking is a list: count what's there, buy the gap, done.

It also makes your costs visible. Once you know what each stay uses, you know what each stay costs in supplies. That number belongs in your pricing, which is why this guide sits with the money guides.

Start with Airbnb's essentials

Some items are not optional. Airbnb's help page on essentials lists what guests expect: "Toilet paper", "Soap (for hands and body)", "One towel per guest", "One pillow per guest" and "Linen for each guest bed" (help 2343).

The same page warns that listings with the essentials option selected that "don't actually provide the items" may face penalties, including removal from Airbnb. So running out of toilet paper isn't just awkward. If your listing says you provide essentials, it is a gap between your listing and the stay.

Airbnb's hosting checklist makes the same point another way. It suggests you "Have a few extra sets of sheets and towels on hand" (help 1189). That is a par level in all but name.

The items to track

Here is the list I'd start with. Add anything your home uses that guests would notice if it ran out.

Linen and towels work a little differently from the rest, because they come back. I cover that below.

Step 1: work out usage per stay

Usage per stay is how much of an item one typical stay gets through. You can estimate it, but it is better to measure it.

The simplest way:

1. At the start of a month, count each item and write it down.
2. Add up anything you buy during the month.
3. At the end of the month, count again.
4. Usage for the month = start count plus purchases minus end count.
5. Usage per stay = usage for the month divided by the number of stays.

After two or three months you'll have a decent number. It will change with your guests. More guests per booking and longer stays use more. A month of couples on short breaks uses less than a month of families on week-long holidays. If your bookings change a lot by season, keep a summer number and a winter number.

Ask your cleaner to help. They see the cupboards at every turnover, and a quick note of what they topped up is the cheapest way to measure usage.

Step 2: set the par

The formula:

Par = usage per stay × stays until your next restock + a buffer.

The stays until your next restock depend on how often you restock. If you restock once a month and you have eight turnovers a month, that is eight stays.

The buffer covers the things you can't plan for. A larger group than usual, a guest who uses a whole roll of kitchen roll mopping up a spill, a delivery that arrives late. How much buffer is a judgement. I'd start with a few extra stays' worth for anything guests would notice straight away, like toilet roll and coffee, and less for things that run down slowly, like cleaning sprays.

Step 3: the buy quantity

At each restock, count what you have, then:

Buy = par minus what you have now.

If you have more than the par, buy nothing. Round up to whole packs, because you can't buy half a pack of dishwasher tablets. Over time you can also round to the pack sizes that are cheapest per unit, as long as you have room to store them. Airbnb's checklist suggests you "Bulk-buy amenities to offer guests" (help 1189), and a par level tells you how much bulk you actually need.

A worked example

The numbers below are invented to show the arithmetic. They are not data about what guests use. Use your own counts.

This example home restocks once a month and has 8 turnovers a month. The buffer is 2 extra stays' worth.

So in this example the shopping list is 18 rolls, 45 coffee pods, no dishwasher tablets and 30 bin bags, rounded up to whole packs.

If you'd rather not do this by hand, the free restock and par level calculator takes your guests, stay length and turnovers per month and gives you a par and a buy quantity for 15 common consumables. It keeps one stay spare as its buffer, so raise the par by hand for anything guests would notice straight away. Treat its usage rates as a starting point, then replace them with your own counts once you have them.

Linen and towels

Linen doesn't get used up at the same rate. It goes round in a loop: on the beds, in the wash, back on the shelf. So the par for linen is about how many sets you need in the loop, not how many you use.

Think about where each set is on a turnover day. One set is on the bed, dirty. One goes on the bed, clean. If your laundry takes a day or two to come back, you need at least one more set on the shelf while that happens. Then add spares for stains, damage and the set that goes missing. Do this for each bed, and for towels for each guest your home sleeps.

Airbnb's essentials list asks for "One towel per guest" and "Linen for each guest bed" (help 2343). That is the minimum on the day. Your par is what keeps you at that minimum when the laundry is late.

Linen also wears out. Count it every few months and replace sets that are thin, stained or torn. A tired towel is one of those small things guests notice.

Consumable cost per stay

Once you have usage per stay, cost per stay is one more step.

Cost per stay for an item = price per unit × usage per stay.

The price per unit is the pack price divided by the number of units in the pack. Add up every item and you have your total consumable cost per stay.

Continuing the invented example, in your currency: a pack of 24 toilet rolls costs 12, so one roll costs 0.50, and at 3 rolls a stay that is 1.50 per stay. Do the same for every item on the list and add them up.

This number is worth knowing for two reasons. It is a real cost of every booking, so it belongs in your break-even and pricing sums along with cleaning and laundry. And if it creeps up over a few months, it tells you something has changed: prices, guest numbers, or supplies walking out of the door.

Keeping it running

A par level only works if someone counts. A few habits that help:

• Put the count on the turnover checklist. The cleaner notes anything below a set level, so you see it before it runs out.
• Use a low-stock line. For each item, pick a number that means "order now", well above zero.
• Keep the store tidy. Things are easier to count when each item has its own shelf or box.
• Review the pars every few months. As your bookings change, so does usage.

Airbnb's guide to preparing your space suggests you "Follow the same routine before every check-in" (resource 656). A restock check is part of that routine. For the money side of each booking, the guide on pricing around the host-only fee covers what Airbnb takes before you see a payout.