do you have prepplus? i can't see it

Without looking at what the program websites say, it's hard for us to be sure, but I would guess that GRE-blind means they won't consider GRE scores as part of the admissions process at all.

You're supposed to describe it, so 300 characters should be sufficient. In other words, don't do either of the above.

my take is that practice tests as early as 1-10 are not going to be useful to you. you're unlikely to do all 87 PTs anyway, so just start with the 40s if you're worried about running out of material