Don’t assume that all investors are the same, just because their money is always the same color. Every entrepreneur should do the same due diligence on a potential investor that smart investors do on their startups. Check on their track records, values and management style. Taking on an investor is a long-term relationship, like getting married, that has to work at every level.

Let’s just say that every investor is different, without trying to define what is good or bad for you and your startup. Investors are human and subject to human tendencies, whether they are your rich uncle, an angel investor with personal funds or a venture capital investor with institutional money. Here is a summary of some key investor stereotypes that generally need to be avoided:

I’m not talking about the Shark Tank TV show, but some might say the panel fits the definition. While the majority of investors are looking for a win-win deal, there are investors who like to prey on entrepreneurs who have little financial experience, don’t read the term sheet or are simply desperate for a deal. Seek out advisors to help you avoid these investors.

We all know that startups don’t have money to fight in court, so it’s easy for a few unscrupulous investors to jump to the conclusion that intimidation and lawsuit threats can improve their returns and control after the money changes hands. Here is where checking the track record pays off. Don’t assume you will be the exception.

These are investors with such massive egos that they expect to dictate both the terms of the investment as well as all future strategic decisions of your startup. Unless you are preparing to work for Donald Trump someday, I recommend that you skip this investor in favor of a more equal partner.

Negotiating terms is normal before the investment, but once the check is cashed, you don’t want to be second-guessed on every action. Be wary if the term sheet is a document longer than your business plan. Violation of abstract clauses may be used as a way to push you out, take over the company or pull the investment.

Coaching should be expected and appreciated, but you don’t have time for constant tutorials on how to run a business. A good advisor and mentor will tackle questions and then offer key insights. If an investor spends more than a day at your office before the check is written, it may be time to check your patience meter.

These are “wannabe” investors who don’t have the means, or former entrepreneurs who don’t want to leave the arena. They always have one more issues to investigate or another set of questions, but never bring the checkbook. After a rational allocation of your team’s time, ask for a definitive close and be willing to walk away.

Many wealthy people make poor startup investors. They have long forgotten (or never knew) the challenges faced by a startup business. Many great real-estate people and doctors fall into this category. A synergistic long-term relationship in your business is not likely. Ask them for an introduction to wealthy business friends.

These are people who rarely invest their own funds, but promise to find the perfect match and live off a percentage of the action and preparation fees. They may be licensed investment brokers or consultants cold-calling real investors. The challenge is performing due diligence on the real investor.

Proactively seek out and build relationships with investors who interest you, rather than passively wait for potential investors to approach you. Finding investors is best done by talking to peers and attending networking events. Cold calling or emailing strangers will likely get you a sampling of all the eight stereotypes defined here.

Finally, you need to learn what investment terms make sense for your startup and craft your own term sheet, rather than rely on one being presented to you. Start with some legal advice from a source you trust. Do your homework and networking, but don’t chase investors like a one-night stand and expect it to lead to a mutually beneficial long-term relationship.