If you do not lack of money, you can try the sale of large equipment, because of high profits, of course, the main contact with the big leaders, because the equipment is expensive big leaders are to ask. But expensive equipment is not to be frequently updated, that hospitals can not stand.
Personally, I suggest that you start with a small one, after all, just do this, slowly accumulate experience, after all, to feed themselves is not. Encountered more people, a wide range of small markets are eaten through, you can try to turn the big market sales of large equipment, so perhaps do better.
Of course, there are some factors of luck, maybe you do a large equipment sales is very successful, but who said this thing of luck clear?