A model with no fleet and no proxies: you talk about a tool, someone subscribes through your link, you receive a share of what they pay.
Who it suits
People who already have an audience that asks about tools: a marketing channel, an arbitrage community, an agency chat, a blog about automation. There the recommendation is natural, because it answers a question that was asked.
Who it does not suit: anyone planning to blast the link at cold contacts. That fails for the same reason all cold advertising without trust fails, while working perfectly well as a way to collect complaints.
Working out the value
Income from one referral is their payment times your share times the number of periods they stay. The last factor matters most: someone who renews for a year is worth several times someone who leaves after a month.
Which leads to a non-obvious conclusion — it is in the affiliate's interest that the referred person actually succeeds. Referring everyone indiscriminately is a one-payment strategy.
What actually converts
Specifics from your own experience: what you set up, what worked, where you got stuck. What does not convert is a retelling of the product page — the reader can read that themselves, and it is not what they came to you for.
Realistic scale
This is rarely a primary income and works well as a secondary one. For a channel of a few thousand readers in the promotion space it usually covers your own subscription and a little more. Estimate it in advance: if only a handful of your audience could ever be customers, treat it as convenience rather than revenue. Terms are on the partner page.