Rankscale is one of the most affordable monitoring trackers — from around $20/mo on a credit model, covering a wide range of AI engines. If you want broad, ongoing tracking on a budget, it's a strong option.
meraGEO competes on the same 'cheap and simple' instinct but with a one-time model: a free scan, then a $19 report that includes the fixes. Over a year, $19 once is far less than ~$240, but Rankscale gives you continuous tracking across more engines for that price.