There are down payment programs for duplexes, i have not searched or tried to do a 3-4 unit property. 

@Mitchell RosenbergAnother approach is the elimination method.

However, finding properties that would cash flow with a 20-25% down payment on 400k property has been challenging.

BRRRR method is also a great way to go - good luck!  

Used houses in the area sell anywhere from $75-125 a square foot.These are long term rentals that I do not plan to sell.I am reading the Rental Property Investing book and implementing the method that focuses on cash flow and that strategy states you need to have $300 cash flow per month, per property.

During construction you'd have minimal payments, either IO or accrued.

Year 0: ($2,000 - $1,700) x (1 + 2%)^0 / (1 + 5%)^0 ≈ $300 in today’s buying power.Year 5: ($2,000 - $1,700) x (1 + 2%)^5 / (1 + 5%)^5 ≈ $260 in today’s buying power.Year 10: ($2,000 - $1,700) x (1 + 2%)^10 / (1 + 5%)^10 ≈ $225 in today’s buying power.Year 15: ($2,000 - $1,700) x (1 + 2%)^15 / (1 + 5%)^15 ≈ $194 in today’s buying power.So, if you purchase property in a city where rent increases at a slower pace than inflation, the amount of goods and services you can buy will decrease over time due to inflation.Here is what I recommend:Purchase in a city that possesses the following characteristics.Significant and sustained population growth.Rapid and sustained appreciationBalance negative cash flow, interest rate buydown, and increased down payment to create an acceptable cash flow situation today.Refinance when rates fall to increase cash flow.

I’m close to saving up for a down payment but it’s taking forever!

You should have 25% down payment + closing costs, + an oh Sh*t fund on top of that. 

Right now, you have to be able to source off market properties or be willing to force cash flow with large down payments.