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One-time payment invoice software: how the math works

"One-time payment" sounds simple, but it's worth checking what that actually includes — updates, device limits, support — before assuming it's the better deal. Here's the honest version.

By the QuestMart team. Updated September 19, 2026. 6 minute read.

Get Invoice Studio — $70 Jump to FAQ

What one-time payment should include

A one-time price is only a good deal if it isn't a stripped-down trial in disguise. With Invoice Studio, $70 once includes:

The one thing the licence doesn't allow is reselling or redistributing the file itself — which is a fair restriction on a $70 purchase, not a feature limit.

The break-even math

Monthly planBreak-even vs. $70
$15/month~4.7 months
$20/month3.5 months
$29/month~2.4 months

After the break-even point, every month on a subscription is money the one-time purchase would have saved. Over five years against a $20/month plan, that's the difference between $1,200 and the single $70 purchase.

What's deliberately not included

Keeping the price low and the payment one-time means Invoice Studio doesn't include things that require ongoing server infrastructure to run: automatic email sending, payment reminders, or a cloud sync between devices. Those cost a hosted vendor real, recurring money to operate, which is part of why they're billed monthly elsewhere. If you need them, a subscription tool is the more honest fit — see our full subscription-vs-one-time breakdown for where each makes sense.

Is the price fixed forever?

$70 is Invoice Studio's current launch price, down from $99. Once you own a copy, updates within version 1 are free — the price you pay is the price you keep paying, which is zero, for as long as you use it.

Buy it once

Buy Invoice Studio — $70, paid in BTC, ETH or USDT, unlocked automatically the moment your payment confirms on-chain.

Frequently asked questions

Are updates really free after I buy?

Yes, updates within version 1 are included at no extra cost.

Is there a device limit?

No — the licence covers commercial use on as many of your own devices as you like.

What exactly can't I do with the licence?

You can't resell or redistribute the file itself. Using it for your own client work, on your own devices, is fully covered.

How do I pay for a one-time purchase like this?

Invoice Studio is purchased in BTC, ETH, USDT (ERC20) or USDT (TRC20). The download unlocks automatically once the payment confirms on-chain.

One file. One payment. Every invoice you will ever send.

Invoice Studio: 150+ currencies including crypto, 7 languages, 4 templates, offline and private. Pay once, $70.

Buy Invoice Studio — $70