im at level 97 now, and have $300m coins right now, so i will be able to complete this no problem, without spending any real money. im on day 8 and havent spent any money, and had virtually zero activity for 2 days when i ran out of money the first time doing the wheel game. and then after clicking on all the dailies, i was back up to $50m again even after being at zero when i woke up. On one device i ran out of money, but when i went to the league wall, i was able to get several million from my other device posting league bonuses all night. then when i sleep i just let both devices run all night. with speedy spins, ive not run out of money, but i also set my alarm for every hour and go do the freebies/shop bonus, watch videos for more coins, etc.
plus i lost all my money by level 50 on that one. I was playing the wheel game mentioned in several guides but that one required babysitting as well. plus if you have 2 devices, you get tons of small jackpots, which if you go to the league wall, you'll get $100k for each jackpot win, so i joined the same club on 2 devices, and between the 2 devices i never run out of coins. Speedy spins will keep going with no babysitting.