Set up small bookkeeping business network. Using Windows 10, Quickbooks, Drake, and Office 365-4 work stations

Job ID: 30867566

Budget: $15 – $25 USD

I currently have 2 mix and match computers in office that use the files residing on the computer used by accountant over LAN. Programs mentioned in project name are used. I would like to set up something more consistent and secure. Definitely need new hardware, including some kind of firewall that meets IRS/FCC requirements as well as good and secure backup solution.
I have 30 years of experience (undergraduate in CIS in the 80s) completing hardware and software upgrades and integration, but have been working in another field for the past 10 years and got behind with technology.
I need someone to consult with that is up-to-date and knowledgeable with small business networking to guide me through purchase and setup and configuration.