Friendship

This isn't just about whether the two of you are friends, it's about how well his/her goals, values and responsibilities are aligned with yours. Take a look at the person's personal life and how stable it is, consider carefully if the person is actually a good person, a good friend, not just how well you get along with the person. You might get along with someone well but when you consider things closely, the person might not actually be a true friend, he/she might not be capable of having your back when it truly matters. So, to avoid personal problems that can easily complicate your business, it is best to look well before you leap and consider how good a friend the person is. before going into partnership with him/her.

Trust

This should be obvious to many entrepreneurs but many times, entrepreneurs choose people they don't fully trust as business partners for one reason or the other. For one to be your business partner, there must be trust between the both of you. Choosing someone you don't trust to be your business partner is simply a recipe for business disaster.

Consider Consultancy

This is more or less the next best thing to do to avoid the cost of hiring someone as an employee when you can't afford to. You simply hire the person as a consultant rather than hiring the person as an employee. This is also an especially useful alternative when dealing with people you don't consider entirely trustworthy enough to go into a partnership with. Since you can't afford to either offer them a partnership or hire them as employees, you can simply hire them as consultants to save cost. It is not always the best idea to offer every tom, dick and harry that is 'good at the job' a partnership because you can't afford to hire them as employees; you can simply hire them as consultants and avoid giving away a part of your company only to regret it later.

Consider Strengths

The strengths of your business partner should complement your weaknesses. It doesn't make business sense if both you and your business partner have weaknesses in the same areas, one has to complement the other, or at least not be as weak as the other in the same areas. For example, if all your business partners including yourself are good at sales but weak at executing on an operational level, it will only spell doom for your business in the near future. It's much better to keep some balance and bring in partners who will complement each other's strengths.