The #1 problem would be: people have never heard of you and you’re small. Why should they trust you over a more established competitor?
#2 is limited budget (unless you’ve got big fat funding, of course). Limited budget you can throw endless money at awareness campaigns. That means it’s you, the sales person, out there meeting folks. Which is a lot of fun, but it’s hard work, for sure. 🙂
#3 I would say it takes longer to close a sale (at least in B2B SaaS), because people are unfamiliar with you and your product. They want to like you, but they obviously also want to make sure you’re legit.