1). Work with better clients. You can have invoice collection problems at $50k, too, but they're much less likely than at $500 and you have much better options for... escalation methods at that point.

2). If you're not a bank, stop taking on so much credit risk. Businesses can deal with substantially sterner payment terms than you'd think to offer. If your clients balk, see #1. (Thomas has some suggestions here, too, many of which reduce to "Work for Thomas' clients and charge enough that dealing with their purchasing processes is worth your headaches rather than chasing deadbeats for Snickers money.")

3). Showing up on iamachumpconsultant.com will not enhance your professional reputation, bill rate, or client pool.