Just wondering if floor jacks and/or straps are necessary tools for me to purchase.

I'm doing about 1200 s/f, and want to install it the best I can. In what situations are these tools used/required?

Those tools can come in handy, especially on certain types of floors. Straps are handy for glued-up floating floors and some glue downs, although on direct glue-downs, I'll use blue tape instead of strap clamps. Floor jacks work good for cinching up tight the last few rows in a nail down floor. That being said, I think there are simple alternatives that don't require buying tools you may never use again. You can make your own wedges while installing a nail down floor to straighten a crooked board. And taping direct glue-downs together is a tried and proven installation method recommended by many flooring manufacturers. Driving a screwdriver into the subfloor to pry over a board will work also for a nail down floor. And a pry bar can work to tighten up those last few courses in a nail or glue-down floor as well. Those tools are handy but not absolutely necessary.

Thanks for the detailed response - I'll hold on to my cash for now and invest later if they seem needed.