It depends on the skill set. 

A lot depends on the amount of work scoped, the state of the code (and type), and the projected frequency of issues, fixes and releases. Well-documented code using common language and techniques will take less time and therefore cost less to maintain, support, and develop additional features to. If your customers are enterprise level there is also higher risk involved. Anything finance related has security and privacy issues and that experience and background accountability is also something to consider. Hiring the cheapest isn't always the bargain one thinks it is with such apps. Hope this helps! Sent from my iPhone

Logan calls attention to basic considerations you need to understand and manage. That said, we've found it productive when it comes to this sort of work to enlist interns who are fluent and experienced in the type of software and tools we're employing to support our landing page and MVP. The work that you've described as part of your requirements would not seem to require a 24/7 commitment and may possibly be best handled via a P/T role. Nonetheless, you should manage this type of relationship based on Logan's recommendations; it's prudent and it's smart. All the best to you, JS