Earlier in the summer, Fenwick hosted a program for new angel investors with RockHealth. As part of the event, Ash Fontana of AngelList presented a primer for new angel investors that included a dozen dos and don'ts that are worth repeating.

Don't recommend a deal you wouldn't invest in to another angel – not only will it hurt your reputation, it might hurt the entrepreneur's ability to approach the investor from another point of entry.

Do look for teams of two to three founders, optimally one who can build and one who can sell. Avoid founders who have never sold anything.

Don't be tempted by non-standard investment models by positioning yourself as a hybrid investor/consultant or investor/incubator. Your competitive advantage as an angel is that you are "first and fast" with capital.

Do beware of companies with outsourced development. The company should have control of the technology and the product.

Don't bother asking a company for a business plan. No one does them anymore, and they are always based on guesswork even under the best of circumstances.

Do say "no" fast. It's not wrong to stop an entrepreneur in the middle of a pitch if you know it's not the right deal. Don't be afraid to say "no" at a meeting, and when in doubt, say "no."

Don't spend longer than two weeks evaluating a deal. You should be able to close a deal within four to twelve weeks.

Do remember that the most probable outcome for any start-up is that the investors and founders will stop funding it, and it will just die.

Don't expect to get a board seat as an angel investor. That's not the role of angels.

Do invest with other angels whenever possible. It's harder for a founder to run from 20 people than it is to run from one person.

Don't invest in companies that are selling more than 20 percent of their equity in the seed stage. There's going to be too much dilution down the line.

Do check out Venture Hacks' write up from the Y Combinator AngelConf for more angel investing insights.

And most important of all, do assume that as soon as you write a check the money is gone. Angel investing is not about making money, it's about being a patron.

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