OK here's where the extra tool cost comes into play. You will need a crimp tool for these terminals. However, as usual, I have located a very good value in an MC4 crimping tool (not the tool pictured). A pro who does this every day for a living would not use this tool because it is more tedious and time consuming than the more expensive pro-grade versions, which utilize a locator assembly,but for the money this tool preforms very, very well.
In full disclosure I imported a reasonably priced MC4 die set and crimping frame from Taiwan and while the dies are not pro-level you're not paying pro level pricing either. The tool represents a decent value for the budget minded boater at $46.95 (CURRENTLY ON SALE FOR $36.00).
Compass Marine MC4 Crimp Tool(LINK)