$500 000 seems incredibly high for a start up. What exactly are you getting for that $500 000?
I have a friend who opened his practice with a $250,000, but a $500K loan is reasonable. It may cost $50,000+ to outfit a practice with the basic equipment and furnishings to start.
A good business plan should have 2-years worth of operating costs in reserve, which covers salaries and lease.
The office lease: ~$100,000/year
Your salary: $100,000/year or less (base pay)
Insurance: $20,000/year +/-
Office staff (2): $70,000 +/- (including benefits and health insurance)
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about $290,000/year operating costs
$650,000 is a comfortable estimate to allow your business to grow and then take off. If you're lucky and the practice takes off like a rocket, pay the loan back early!
You can calculate the number of patients and surgeries you need based on RVUs (about $34 per RVU) for your practice to stay in business. On average, office visits can generate about 2-3 RVUs for new patients and 1-2 RVUs for return patients.
Let's assume 3 RVUs or $102 for a new patient and 2 RVUs for a return patient or $68. At first, all your patients will be new and then eventually have a mix. When your practice is up and running, let's say your goal is to see 30 patients a day with 20 return slots and 10 new slots. You'll generate on average, $1360 from seeing return patients and $1020 from seeing new patients. That' about $2380/day in billing. You'll be seeing patients 4 days a week and operating 1 day a week. Let's say you mainly do cataract surgeries. On average, you get $650 (varies by state) per surgery. You are doing 4 surgeries per week and generating $2600 in surgery billing. This will give you $12,120 per week in billing or $48,480 per month (can be less if your practice is not good at bill collection). Considering holidays and vacations, you'll work 11 months per year generating $533,280/year.
From this revenue, you'll invest in 1) growth of your practice, 2) expanding your billing/collection services, 3) marketing, 4) your staff salaries, and 5) your income.
The above is only a rough estimate, but gives you an idea what it takes to survive.