It's worth it, don't worry. Just don't Time travel whatsoever!
Spend about 500k at the least. With TBT, and other friends you may have, you'll find a good price over the amount you paid.
You can place the turnips on the ground all over your town. I know it's messy, but it's worth it. If you're trying to get perfect town, just bury the turnips.
You'll have bunches of 100 turnips. 100 is the max amount you can hold in one bunch. So you gotta order them in increments of 100.
I spent 100 mil on turnips. I'd spend more, but my towns covered in paths. I have barely any space =/
Good luck!