Hey Thomas,
I'm an investor and agent here in Phoenix. My partner and I own a portfolio of STR's here as well as do flips and mainly work with fix and flip investors.
Right now in the market we're seeing 50% of sales coming from the $350k-$550k sales price point and another ~25% of sales coming from the $1.8M-$3.5M range. Knowing that you'll have a good amount of eyes on the property at your ARV of $3.5M, I think you would be able to get it sold in a decent amount of time and save some holding costs.
Rates are coming down, but in that price point most buyers will be coming with cash or don't care about the rates as much.
So yes I think this is a good deal, not sure how many partners you have on this deal but I think your decision depends on how much each of you need to make on the deal for it to make sense and how quickly you all want the return.
As an STR you can definitely cash flow but you'll just need to make sure you can make that balloon payment. After that, this seems like a really great return on your investmenrt for the long term as an STR. So again, I think that comes down to, are you all prepared to make that balloon payment, can you hold on and get to where you have "passive" income coming in from the STR, or do you want to get in and out quickly to make a good chunk of change.
Would love to connect sometime, feel free to reach out. I'll send you a connection!