Straight Medicare is required to pay you within two weeks of receiving charges. If you're not getting paid by then, either the patient has a managed plan, your billers are doing something wrong, or the patient doesn't have Medicare B to cover your charges. I have plenty of patients with pending "Medicare" balances on our monthly report, but they don't have part B so what it really means is they're uninsured from my perspective. So we rarely get paid by them.
If patients don't pay their deductible they don't pay their deductible. I'm not going to go after my patients and send them to collections (which rarely works) unless they're just flat out hostile.
Some patients we just won't get paid for--it's the downside of traditional fee-for-service. It's just part of the cost of doing business, and always has been in medicine--some patients just won't be able to pay. On the upside, we still generally make significantly more than an employed doc in the same circumstance, where the hospital eats that loss (but also takes a large cut of the physician's profitability).
I find it best to just take a brief look at my monthly reports from my billers, then file them far and away. Perhaps once a year I ask about delinquent accounts, but my billers seem to be competent and are motivated to collect where it's feasible (it's how they get paid after-all).
I pay my taxes quarterly. Paying on one bunch either means forking too much money over way too early, or at tax time and getting hit with a lot of late fees, as quarterly payments are required unless you're paying taxes elsewhere (and to a substantial degree).
I used to have an accountant. The first one charged about $1000k/yr, but he wasn't very responsive. Then I went with a recommended one who charged $2k, but very responsive. Then they increased their rates to $3k. I felt I was doing most of the work anyway with filling out their "packet," and I don't have a complex revenue stream (just collections + director stipend, a little bank interest). I'm also a sole proprietor which keeps things very simple. So I did taxes on my own this year with Turbo Tax back in Feb, and will probably continue to do so. Much more simple, and gives me a better understanding of my tax situation.