Money of course, but not problems! You want an investor who can bring some value to the table, not only cash! And to do so, the investor has to know your sector, not only that s/he heard of it, you are looking for deep knowledge and experience. Otherwise you’re doomed.
Well-intentioned investors can take down a business just out of sheer incompetence of the sector (and for some, also incompetence of their job) and in the process burn a lot of money under the false rule “I put the money I must be able to take decisions.” Bad for their money, but worse for your business.
For as much money that such an investor offers you, you don’t want it!