I do a lot of consulting for people just starting up their own online businesses, or taking their brick-and-mortar online. Regardless of the differences in their location, product, or budget, there always seem to be some of the same types who pop up. These potential clients are pure poison for a small business, often taking up much of the time and resources a small business or freelancer needs to stay afloat.

They aren't interested in doing any work

One of the biggest problems with a client is getting them to understand that there's no one-click way to get their business online. Clients will have to supply you with information about their business, regular feedback on your progress, product descriptions and photographs, and more.

A client who thinks they'll be able to hand over a cheque at the beginning and get a finished product at the end with nothing on their part in between isn't worth having - they're too much hassle and too much of a time dump.

They think you can do everything

An expansion on the client above, this client expects that you will be the one to take their product photos, write their business history and employee biographies, build their web layout, set up all their email accounts, and design their logo.

The odds of finding a development team - especially a smaller one-, two-, or three-person group - that can do everything under the sun is very low, especially in the short time frames that these clients often expect.

Your business may offer a number of other services, but never work with a client who assumes you're a one-stop shop when they only ask about one thing. Your skills vary, and you shouldn't be expected to be a master of all trades for the payment of one.

They offer stock options as payment

The client has a billion-dollar idea. They think they're the next Mark Zuckerberg. All they need is... for you to develop the entire high-security million-user backend for them. Once you're all done with that and the money starts pouring in, you'll be rich beyond your wildest dreams thanks to the stock in the company they paid you.

The best advice for clients like these: run. Most billion-dollar ideas don't come from people who have no idea how to do their development themselves. Bill Gates, Evan Williams and Biz Stone, and Jeff Bezos all knew more than a little about programming when they started out - any good idea man will take the time to invest a bit of education on his product first.

If you do take on this client, you will be working for free. So don't bother - if they were really interested in their project, they'd secure a small business loan to pay you in the very least.

They offer you more work in the future instead of paying you now

This client "wants to see how well you'll do." They demand all the work done first, and then they'll pay you - if they like it. This is spec work, and you'll probably never see a dime from them.

Unless the client is prominent and respected in the community - and more importantly, someone you know previously and can trust - you have no reason to work for free. Even if they do decide to pay for future jobs, they'll usually offer too little for you to ever make up for the work you've already done for them.

Remember to be a professional

Even if you're not interested in a client's project for any reason, you should still be professional about rejecting them. Don't tell them their project is underdeveloped, underthought, or unreasonable. Don't insult their offer or their idea. Most importantly, don't be rude.

Write a short, friendly email explaining that you're not interested in working on their project. It's not even necessary to explain that you're too busy with other clients - a simple "no" should suffice.

Sometimes, these clients will come back with an increase in how much they offer to pay. However, if they're one of the poisonous types listed above, no amount of money should sway you. After all - they don't run their businesses to make little to no money, so why should you do the same for them?