@Joshua Hughes
In response to this question:
"I am ready to start planning for my second house hack. Every one of my dollars has a goal otherwise it gets spent. so thats why I need to know exactly what to do with Rent checks..and how to go about my second purchase. I want to get two doors (duplex) for my next deal. Will all my rent checks go into my normal checking account?"
Sounds like you are just starting to get yourself organized for bookkeeping for your rental. The lean approach is to use a free software for rent collection (there are a lot of them out there, I used cozy/apartments.com my first 2 years) and a expense tracking system (Stessa gets a ton of positive reviews and I used it for my first 2 years). Now that you know what you're tracking results in your business, my recommendation is to separate your business and personal life. This can be easily achieved by opening a checking account specifically for your rentals (you may also need a separate account to hold deposits depending on your state's rules) where rents come in and expenses go out of.
Creating this separation will allow you to give a job to each dollar like you've done in your personal life. I love that you have a good stock position and some cash invested in a CD but you may want to consider changing your view of that to your personal investing fund rather than your emergency fund. If you have to liquidate your stocks to maintain your rental, there is a very high opportunity cost of losing the compounding of your returns over the life of your investment.
This is where @Paul Vail keeps reiterating the point of being conservative with a healthy cash cushion. Be certain that your personal emergency fund is in a good position (many will recommend 6-12 months of expenses). In addition to the personal fund, many investors will recommend a healthy investment capex/repair/emergency fund (covering major mechanicals and several monthly payments of rental's mortgage).
To give an example of this in practice from a novice point of view... In 2020, COVID enters, stock market falls (reducing your current stock emergency fund). Luckily the market bounced back but if a large repair or capital expense occurred while the market was still recovering, you would have lost money on your stock investment and missed on the potential growth over the past year. Many investors also ran into issues with residents being able to pay full rent, thus another chance of your stock investments needing to save the day. Having an emergency fund specifically for your business may appear to be "losing" you money while it sits earning <1%, however, it could keep you from needing to liquidate other investments that historically will build your net worth over time. As you get more rentals, many will agree that your per property reserve could be reduced as hopefully every singe roof and furnace doesn't go out at the same time and will give you the opportunity to replenish the fund.
To sum up, get your personal and business lives separated and plan your emergency funds based on your own risk profile for each. Once those are well funded, save the excess cash flow from your rental to accelerate your savings for that next investment and get ready for the snow ball. Best of luck!