Not arguing with your attorney, as I'm not one myself, just wondering what his reasoning was on this one.Unless your attorney objects, I'd form a new LLC for your new property and keep the STRs in an S-corp, as your current CPA suggested.

My $0.02 as a new investor is you should form as many deep relationships with knowledgable people as you can.

Don’t trust their pro formas.

Once it's under contract, then form a multi-member LLC for the specific property. 

Generally speaking, projects that require you to be active have better returns at least on the pro forma level.

Should we form a business? 

The seller is going to try to sell on pro-forma, and the purchase price should likely fall somewhere in-between.

Hey Keith,For an SFR LTC deal such as this, I would consider providing the following (in no particular order):AddressPurchase price / renovation cost estimates / ARV or pro forma CAP rateDeal structuring (equity vs loan proceeds)Projected rehab timeframeBeginning date of project (day escrow closes) Projected exit date (expected sale date) Surrounding comps to justify purchase & sale priceEquity distribution project structuring (will returns be a fixed % for GP & LP(s), or is there a waterfall equity return model based upon varying levels of success) Expected ROI distribution date (After exit, and if profits, when can investors expect to get paid)Those are just top of my head, you may not need everything in there depending upon the investors you're looking to approach this deal with.

The rents will form a checkerboard pattern. 

According to legal zoom:"For owners of rental or investment real estate, it’s common to form a limited liability company and transfer title to the property from the individual owner to the LLC.Transferring property to an LLC can limit your personal liability if someone is injured on the property and files a lawsuit against the property owner.