I am a part time real estate investor (own a triplex I rent) with a W-2 job.

It will tell you it "should" be, but the job is for you to know it well enough to tell IT what the pricing should be. 

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with zero or negative relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560, little to no good tradelines, lots of collections & chargeoffs, recent evictions.

I would suggest reading this before you get too far. 

We think it will make a great short-term rental in a very office-space-heavy area.I want to offer her a higher sale price (closer to what she wants) if we can make the deal work for us.Any suggestions?

I like RTA because they come with a factory finish paint job already.

I'm personal friends with the owner and they do a great job. https://www.livindy.co/ 

If you are trying to convert a property under and hoa into an str, your job gets even more complicated as the HOA itself may have its own regulations IF it even accepts it at all.caution: STR market is over saturated in these parts and some of them are shuting down and being converted into corporate housing, mid term rentals, or furnished long term rentals.

However, there may be certain exemptions or procedures available in your jurisdiction to avoid reassessment in specific situations, such as when transferring property between family members.The approach suggested by the tax assessor office, where Aunt A provides evidence that she was only a co-signer and has no ownership interest in the property, could help support your case for avoiding reassessment.

My suggestion to you - Don't buy something just to jump in and have to feed it money every month (ie. negative cash flow).