XFCoder - On-Site Wallet 1.0.5

Allows your users to have an on-site wallet which they can top up with any payment profile (e.g. Stripe or PayPal) and which can be used to pay for any item on your site (user upgrades, Ads Manager ads, eCommerce orders and so on).

Benefits:

Gives your users a convenient method of payment, which can translate to more sales.
You receive funds in advance.
Encourages loyalty, users with prepaid credit are more likely to return and utilize it.
You can run statistics detailing filtered totals of sales or top ups right in ACP.

Features:

Supports all currencies offered by XenForo. Crypto top ups are supported as long as the payment gateway reports back the fiat equivalent (which is normally the case).
Supports recurring payments such as recurring user upgrades or any subscription conforming to the XenForo standard. A cron job processes due renewals.
Supports payment gateway reversals (e.g. Stripe refunds).
You can configure bonuses per user group with a qualifying minimum top up amount (e.g. "VIP users receive a 10% bonus when topping up with $50 or more"). In the case of a payment reversal, the bonus is also automatically reversed.
You can offer bonuses on user registration (e.g. "Sign up and receive a $10 credit").
Allows credit transfer between users. The user can include a note when making the transfer. The user is warned in advance if the intended recipient is banned.
Users can view their transactions in the transaction log, where they can also cancel active subscriptions directly.
Supports credit adjustments (intended for admins and is permission based). Adjustments are logged in the moderator log. Batch credit adjustments are also available (e.g. "Happy New Year $5 bonus for all VIP users").
You can view user credit in the ACP users list, on user profiles and in postbit. Click the credit to adjust it. These are all permission based.
You can view and export transaction details with filters for username, transaction type, purchasable type (e.g. user upgrades or ads), payment profile used to top up, transaction amount and date range. You can view the filtered transactions total (so as to gain insights such as "how much was spent on user upgrades this month").

This add-on is running on a high income production site for well over a year now.