See the Comparison Chart to see if you need the Professional Edition or if the Standard Edition @ $49 is enough for your needs.
You can, I believe, evaluate the Trial version for 30-days with the full feature set of the Pro version.
The Home Edition is unlikely to meet the needs of a DTP professional who uses MainType for their business.
$49 or even $79 is considerably less than $3 a month spread over three years. There is no limit to how long you can use the registered version.
The only question you need to answer is “Does it save me enough time to justify the price.”
I have no experience of using cf FontBase, so I cannot compare them on feature set or ease of use.
See my review page (in my Forum Signature) and my Amateur Videos to get an overview of the features.