Turn-Based Strategy Mode!
The heroines at large can spend their hard earned cash doing lots of things, including donating to local war funds of an area for the purpose of hiring guards and the like to defend. 5E allows for even lesser combatants to fight even dragons, so honestly hiring the common mortals to fight chaos is completely reasonable! As long as you have enough of them. In addition, you'll be able to recruit more powerful entities later on. An example being, the lizard folk, who are now allied to you! I'll be posting rules and info in the 1st OOC post, including how many soldiers you have and where, and the total income you're making, and the total cost per day you pay your own personal Hero Force.
Each territory will attempt to sustain it's own personal military force, which will be the bare minimum which it needs to defend itself. You can hire more soldiers, purchase them gear, and have them act as either a military force attacking or defending territories. When you eventually earn enough Gold to start BUILDING your own properties, you will likely need soldiers to defend your new, owned territories as the forces of Chaos will seek to rape and pillage your land and others. For now, your price range is just buying Guards and their gear. But later on, you might think about buying a Trading Post, or building a small town and collecting taxes! Both of those will cost 5000gp. For the future!
For now, you have your intro to the Strategy mechanic, which is mostly just a singular look at it. The soldiers you hire can be brought with you during adventures, but keep in mind that they're only good at fighting and barely so at that, they cannot sneak and make anything but fighting useless. Mostly only useful for possibly saving a comrade who's been captured.
For now, you don't need to worry about doing any strategy or purchasing of soldiers. Samua and the Mayor can defend against the threat outside the town.