I've thought a little about this,
concern would be that in many major markets, there are massive entities (Kaiser, Catholic Hospitals, Lutheran Adventist, etc) that have enormous buying power & can muscle suppliers to get really cheap hospital supplies etc, and that there'd be high "barriers to entry" because of this.
possibility (I'd think) would be to speak with counties/states that are "medically underserved" to see what incentives they would offer if you were to start a hospital in their area. Maybe federal incentives are available too?
I know there are medical consulting firms that assist in setting up a practice; I think it would be necessary to find someone who knows the details to setting up billing procedures, patient admit procedures, screening employees, etc. May need to pay a hourly consultant for their expertise in this. + if you have a building built, would need to work with a specialty architectural engineering firm that is experienced with designing hospitals specifically. Probably some special contractor experience would be needed, i.e. need to hire contractors who have hospital building/repairing experience.
Not sure what the rules are regarding departments -- if you have to have an OB section/ER/Surg unit, or if you can set up a "hospital" that only does select medical procedures? I'd think a hospital (verus a practice) would have to offer diversified services? I'd suspect this can be done, but your role would be far more managerial/entrepreneurial than medical for quite a while.