I think I found a new faster route that is very safe for the majority of the game and not much can go wrong, but it can be reset heavy at the start.

Day 1 - Set up: 2.7 Coffee, 2 Milk, 2.5 Sugar, $4.00 Price. Buy the middle column for everything. These numbers don't have to be exact, but try to get as close as possible. The goal of this day is to sell out as fast as possible, which can be dependent on the RNG if they buy or not. The temp will always be 51 degrees, and with this price and mixture they will like it.

Day 2- HAS TO BE COLD, IF NOT RESET (colder the better). Set up: Same as Day 1, but price around $4.50-$5.00. Buy 10 cups, 20 coffee, 30 milk, 30 sugar. On this day you will get the money you need for the rest of the game, which will be around $60 (will do more testing on this). Sell at the higher price until you're around $60, if not sold out reduce price to $0.05.

Day 3 and onward- Set up: 1 Coffee, 0 Milk, 4 Sugar. $0.05 Price if not already. Just buy the minimum of what you need as you need it. Most days you will sell 3 cups and you will have to restock sugar. Some days you may have only enough for 1 or 2 cups based on cups or coffee, so then there will be days where you are selling less than 3 cups. Make sure to go as fast as possible when skipping and restocking, as leftover people can buy coffee, even before you close out of restocking, but only once you have bought the item that is out. From here on out its an RNGfest to determine your time. You will either get a cold day or warm day, and that will determine if you sell fast. You should not go bankrupt unless you get really unlucky and lose a lot of coffee.