Answer: A single copy of the Basic edition of Foxhound is limited to monitoring 10 target databases, and the Extended edition can monitor up to 100 target databases.

However, the Extended Edition of Foxhound does not limit the number of separate copies of the Foxhound database that may be created and started using separate instances of SQL Anywhere on the same local network; see Help - Introduction - Starting Multiple Copies of Foxhound.

Note: Here's what the End User License Agreement has to say...

In the case of the Extended Edition, an unlimited number of copies of the Foxhound database may be created and started using separate instances of SQL Anywhere on the same local network, with the requirement that a separate Extended Edition registration key be purchased for each multiple of 10 copies of Foxhound started.

See also...
Help - Introduction - Starting Multiple Copies of Foxhound
What are the differences among the different editions of Foxhound: Rental, Basic and Extended?
Help - Introduction - End User License Agreement