I wouldn't recommend it for a number of reasons. 

I wouldn’t personally recommend it, as office vacancy rates are currently quite high.

I would maybe recommend reaching out to another CPA or two to get an idea of the cost in your area and with your situation to see if you're overpaying.

Left me feeling like a basically have a retail/fulfillment person on my team so I'm a big fan and would recommend giving them a shot, especially if you're in a similar position as I was: Needing to furnish an STR quickly and cost-efficiently. 

We estimate the project will take less than 3 months to complete.I’m exploring alternative short-term financing solutions and would appreciate any advice or recommendations on options that might work well for this type of project.Thank you in advance for your insights and assistance!

Just to be clear, I am not in anyones corner on this one, I recommend everyone always do their own due diligence as part of any deal.

One workaround could be keeping a separate spreadsheet to track your adjusted tax basis accurately and only using Stessa for operational insights.You could also reach out to a cpa and see if they have a specific recommendation for software to use.  

At the current scenario, without knowing anything about you or your properties I will recommend either to look at a loan from your assets using DSCR loan.

If you want to get into MTR or STR I have better markets to recommend.

I recommend you make a video of you entering the unit and documenting exactly how it is found.