@Ryan Prichard , congrats on finding a deal!
Is it under contract or accepted LOI? Either way I would 100% use financing, there is no reason not to take advantage of still incredibly low interest rates with long term non-recourse financing (Fannie/Freddie). There are some good bridge terms out there right now and it's not a bad option, I would just make sure to shop around. Also look into a rate cap if it's a floating rate, SOFR will most likely rise when the Fed hikes the fed funds rate.
For your raise with 75% LTV, assume 70% LTC so you'll need 30% of the purchase price for downpayment, closing costs, fees, inspections, etc.
(2) A very common structure is to pay an annual preferred return between 6-9%, with a split of cash-flow above the pref 70/30+/- LP/GP . After capital is returned 100%, profit is split 70/30 LP/GP or whatever %'s you and your investors agree to. You can add different classes of units, more water falls, the sky is the limit. Simple is often the best, however.
(3) It depends on the project, such as the vintage, the scope of the renovation, market conditions, etc. I prefer to over capitalize to the point where it doesn't effect returns materially.
(4) Whatever your accountant says is the best, but Quickbooks works. If you are doing property management many of the functions of property accounting will be included in your property management software.
(5) There has to be a captain of the ship. While major decisions after the purchase may be appropriate and fair to give members a vote, or even the ability to veto certain actions like a sale, once the decision has been made it's the responsibility of the managing member (assuming you are using an LLC that is managed by a manager and not by members) to carry out the business plan. When we present a deal to investors it's made clear that our team is running and operating the project. We always welcome input, suggestions and assistance, and 100% transparent but at the end of the day the buck has to stop somewhere.
(6) I agree with @Jonathan Twombly , you are offering a security, although most like one exempt from registration - but you still have to file for the exemption. I also highly recommend that you bring in a partner that has done multiple successful syndications, even if he is mostly just advising and assisting in asset management, it would be worth giving a slice of the GP to have someone in the deal with experience.
Good luck with the deal!
(Not legal or financial advice)