I wouldn't bother with one my father went without one when he started up. Are you credentialed etc? PM me for more info.
First decide whether you are truly cut out for practice ownership. Running a small business as an added responsibility to being a full-time clinician is not suited to everyone. Then seek all the prevailing advice about how to start-up a practice (there is a ton of it out there in forums and elsewhere), and whether buying a practice or starting up is a better choice. There are certain nuances to ophthalmology practice but much of the start-up advice pertaining to other medical specialties and allied health fields will also be helpful.