It is possible to work with software development companies on one-time projects as well as longer-term engagements; however, the ROI (return on investment) may vary depending on the type of project. Shorter projects tend to produce results more quickly than long-term projects but may not yield the same significant returns over time. Longer engagement periods allow for more comprehensive strategies to be implemented, which could result in higher ROI if done correctly, along with better technologies and innovative strategies.