To make a long story short, for one property you are not going to save $ in the long run and realize materials can take 6-16 weeks to arrive. 

Outside of real estate, I’m a huge sports fan, so you can usually find me glued to almost every game on the weekends.My interest in real estate began as I explored different ways to generate passive income, which ultimately led me to the BiggerPockets community.

Inherently the steps are the same as if you were purchasing with financing save potentially less closing costs and ability to close sooner (if needed).The terms of your offer (ie -contingencies, closing cost splits etc) will determine what is different. 

I would highly recommend finding a lender that does 10% of purchase price down because it will ultimately be less expensive for you.

Do you have a current need for that cash flow generated from the tax savings?

Let them know you are shopping and tell them to give you their best offer (all on the same day), and state you will go with whomever can save you the most money. 

@Laura GenoneI have my own information saved as a contact in my phone and it allows me to text, airdrop, or email my information to people I network with.

We plan to stay in this house for more than 5 years unless another great opportunity arises, but maybe it is best to allocate a bigger portion of savings to our real estate investment savings account than our home improvement savings account for the first few years.

THEN, I plan to purchase the second home using a FHA or conventional loan (3%-5% down), for which I will likely pay the monthly cost out-of-pocket, maybe with some rental income support if it is a duplex.My concern is, I do not want to spend my savings or weigh down my debt-to-income ratio so much so that I cannot qualify for and pay the down payment and closing for the lending on the second home.Questions: - With the first home being multi-family, 75% of the rental income (or potential rental income initially) will relatively either maintain or boost my debt-to-income ratio from lenders' perspectives, right? 

If you want to acquire more real estate I suggest more savings or sell the other property with equity.