The only fixed cost I know off the top of my head is the $1,140 per year server maintenance cost, but we also have iBackup, Symantec Endpoint Protection, Microsoft 365 that we use for email, contacts, and calendars, and I believe a few other small quarterly charges for some kind of virus protection or hosting services. I can look when I get to the office tomorrow and give you a better idea then.
Software costs us a lot more than IT maintenance, though, that's for sure. We use QuickBooks Accountant for all of our standard monthly services (financials, payroll, etc.) and we have to buy multiple licenses each year when we upgrade. My employer and I are QuickBooks ProAdvisors, which does cost a bit but comes with one license for most of the QuickBooks products they offer and the more certifications you attain the more savings you can get on multiple licenses and licenses for your clients who need them. Not that I'm all that big of a fan of QuickBooks, but it's definitely one of the cheaper products.
For tax prep, we currently use UltraTax CS and have used Drake in the past. I believe Drake cost around $9,000 for the year we used it but we were all very unimpressed with it so we won't be going back to that software. UltraTax cost us around $20,000 for 2010 (hence the switch to Drake for 2011), but when we came back over from Drake my employer talked the Thomson Reuters rep into giving us 2013 free with our purchase of 2012. If you'd be interested in UltraTax as your tax prep software, Thomson Reuters does offering annual financing, so it is still manageable (just overpriced in general). If it wasn't cost-prohibitive to us as a smaller firm for now, we'd likely be using Creative Solutions for everything (we did when I first started right before the recession hit). My employer, being the stereotypical definition of a CPA, is a bit obsessed with saving money and having things run smoothly as cheaply as possible (without purchasing sub-standard services or products), so I'm fairly certain our use of services and software probably cost around the same as any new CPA firm startup with a few employees that doesn't want to get into anything too expensive yet.
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