Buying Commercial Power Equipment? The 6-Step Checklist I Use in 2025

If you're responsible for buying a portable power station, replacing a backup battery, or adding an EV charger to your office parking lot, this checklist is for you. I'm an office administrator for a 40-person company. I manage facilities purchasing for three locations, which adds up to roughly $180,000 a year across maybe two dozen vendors. I've been doing this since 2020. This isn't a theoretical guide. It's the exact process I used when I had to size a battery system for a small off-site event and then handle an EV charger install at our main office.

There are six steps. Follow them in order, and you'll avoid most of the expensive mistakes I've already made.

Step 1: Write down the equipment you actually need to power

Don't start with a battery catalog. Start with a notepad. I know this sounds boring, but it's the step that saves you from buying a $600 portable station that can't run your coffee machine.

For each device that needs power, write down:

• The watt draw. It's usually on the label.
• How many hours you'll run it.
• The math: watts × hours = watt-hours (Wh).

Here's a real example from our office:

• One 60W mini-fridge for 8 hours: 480 Wh
• Two 65W laptops for 6 hours: 780 Wh
• One 10W router for 10 hours: 100 Wh
• A 50W printer for 2 hours: 100 Wh

Total: 1,460 Wh. That number is your starting point. I almost bought a Bluetti AC60 portable power station before doing this math. It's a solid little unit, but it's 403 Wh. It would have lasted less than five hours in that scenario. I would have looked like an idiot in front of operations.

Checkpoint: You have a list with watts, hours, and total Wh for every load.

Step 2: Compare usable capacity and continuous output, not marketing numbers

Once you know your total Wh, compare it against the battery's rated capacity. If you see a spec like 403 Wh, that's 0.403 kWh. A lot of people get confused by the units. One kWh is 1,000 Wh.

This is also where I had to search 'Tesla Cybertruck battery capacity kWh,' because someone in our company asked if we could use one as a mobile generator. The answer: the Cybertruck has roughly 123 kWh of battery capacity, but it's a high-voltage vehicle system. You can't just plug a 12V appliance into it without additional equipment. It's a vehicle, not a portable power station. The Tesla Powerwall is a home and commercial battery at 13.5 kWh. And the Bluetti AC60 is 0.403 kWh. These are three different product categories.

One more thing: don't shop for the largest number. Jupiter is the largest planet in our solar system, but nobody uses Jupiter to power a conference room. When you compare battery capacity, look for enough usable capacity plus a continuous output rating that's above your total wattage. For inductive loads like a fridge or a pump, keep the peak output in mind too.

Checkpoint: You know your minimum usable capacity in kWh and the continuous wattage rating you need.

Step 3: Read the battery warranty like a lawyer

If you're thinking about Tesla, you've probably searched 'Tesla battery warranty' before. Tesla's Powerwall warranty is 10 years. The Cybertruck battery warranty is 8 years or 150,000 miles, whichever comes first, and it covers capacity loss below 70%. Those are the headlines. But the details matter.

For a portable power station, the warranty period is usually shorter, anywhere from 2 to 5 years. Ask these questions:

• What capacity loss is considered normal? 70%? 80%?
• Does the warranty cover the battery, the inverter, or both?
• Who pays for shipping? A warranty can be practically worthless if you have to pay $200 to ship a heavy unit both ways.
• Do I have to register the product within a certain number of days?
• Is the replacement battery covered for a new warranty period, or only the remaining term?

There's a legal layer here too. The FTC enforces warranty requirements through the Magnuson-Moss Warranty Act. A warranty must say whether it's 'full' or 'limited,' and the terms must be available before you buy. If a vendor can't show you the warranty document before checkout, treat that as a red flag.

Checkpoint: You have a written warranty document with retention limits, throughput limits, and the claim process spelled out.

Step 4: Plan the EV charger installation before buying the charger

EV charger installation is not a plug-and-hope project. If your office is in Montgomery County, MD, like ours is, the process has an extra layer: permits and inspections.

In my experience, an EV charger installation in Montgomery County starts with a licensed electrician pulling a county electrical permit. The county will want to inspect the work, especially if you're adding a dedicated circuit or upgrading your panel. That's normal, and it's actually a good thing. But it takes time. Plan for a few days to a few weeks depending on the local workload.

Also check with your utility before you sign the work order. In Montgomery County, your utility might be Pepco. Utility rebates and demand response incentives can reduce the installed cost, but they often require pre-approval and an approved contractor list. Don't install first and ask for the rebate later. You'll end up with a very nice charger and no incentive.

This is also where the time-certainty premium comes in. In March 2024, we paid $400 extra for rush installation so the EV chargers would be ready for a client event. Missing the event would have cost us far more than $400. If you're defending that decision to finance, call it what it is: certainty. An uncertain cheap solution isn't cheaper when the deadline matters.

Checkpoint: You know the permit cost, expected lead time, panel requirements, and whether your utility rebate requires pre-approval.

Step 5: Build in delivery time for lithium batteries

Portable power stations contain lithium-ion batteries. Carriers treat them differently from a box of paper clips. USPS has specific rules for shipping lithium batteries, and the practical result is that ground shipping is common while air freight is limited. Delivery can take longer than you expect.

Don't promise your team a delivery date until you've confirmed the ship method with the seller. Ask whether the battery ships separately from the rest of the unit. Sometimes it does, which means two tracking numbers and two potential delay points.

If you need power by a date that's two weeks away, a local vendor with stock is often worth the extra cost. I once had two hours to decide before the weekly shipping cutoff. Under time pressure, I went with our usual vendor instead of getting multiple quotes. I didn't love the price, but I loved the confirmed arrival date. A confirmed date was exactly what the CFO wanted.

Checkpoint: You have a delivery date in writing and a backup plan if the first shipment slips.

Step 6: Build a one-page scorecard for finance

As an administrator who reports to both operations and finance, I don't keep purchasing knowledge in my head. I make a scorecard. For each quote, list:

• Unit price
• Shipping and taxes
• Installation cost
• Warranty period and key limits
• Battery capacity, in Wh or kWh
• Continuous and peak output
• Rebate or incentive amount
• Expected useful life or cycle count

This looks like extra work, but it saves time when salespeople start using vague terms. If a vendor says their station is 'environmentally friendly' without giving specific facts, ask what they mean. The FTC Green Guides require environmental claims to be truthful and backed up. A marketing line like 'green power' without context doesn't tell you whether the battery is LFP, whether the packaging is recyclable, or how they handle end-of-life disposal.

Checkpoint: You can compare at least two quotes side by side, and you have a written record for your accounting team.

Final reminders from my mistakes

• Don't size by peak output alone. Continuous output is the number that matters for hours of runtime.
• Don't assume a longer warranty means better coverage. Read the throughput limit and the capacity retention percentage.
• Don't skip the EV charger permit process. It might pass the electrical inspection, but an unpermitted install can be an insurance headache later.
• Don't ignore battery chemistry. LFP batteries tend to last longer but weigh more. NMC batteries are energy-dense but may age faster. Choose based on how you'll actually use it.
• Don't let a random search interrupt your decision. And if you search which planet is the largest in our solar system, the answer is Jupiter. Trust me, I know from personal experience.