Payment in advance means paying for a period of service before it starts, rather than being billed afterwards for time you've already used. Most self storage is paid this way: each payment buys the next block of storage time.
At Wigwam
Our terms (clause 5(a)) say: "We will take the first payment on acceptance of Your order and will take subsequent payments in advance on the invoice date for each Storage Period or other date agreed with You (Due Date)."
In practice, our booking FAQ asks you to "pay for your first four weeks of storage upfront", and we then set up automatic payments. We accept credit or debit cards, not cash or cheques; ongoing payments go through an online card system or Direct Debit. We don't send a bill before each payment; we send an electronic invoice after it.
Two lines in clause 5(a) are worth knowing. "It is Your responsibility to see that payment is made directly to Us on time and in full", and a payment only counts once we have it "in cleared funds". So under clause 5(a), if your card expires or a Direct Debit fails, making sure the payment still reaches us on time is down to you. A payment that doesn't arrive by the Due Date can bring a late payment fee, charged "each time a payment is late or cancelled" (clause 5(b)), and the other steps clause 6 allows. Our terms don't describe any retry or grace period, so ask us what happens if a payment fails, and update your card before it expires.
Payment in advance vs a deposit
They're different money. A payment in advance buys storage time, and if you leave partway through a period, unused days after your notice period are refunded (see pro-rata billing). A deposit isn't storage time at all: it's security, returned at the end, less any proper deductions. At Wigwam the deposit is two weeks' rent at your unit's standard weekly rate, paid when you book.
Related terms: Billing cycle · Deposit · Late payment fee · Pro-rata billing
Related questions: When will I be charged, and why do I pay in advance? · How do I pay, update my card, or get an invoice?