For example, the condition of the apartment.

That’s typically way ahead of the curve. 

:Class A Properties:Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Vacancy Est: Historically 10%, 5% the more recent norm.Tenant Pool: Majority will have FICO scores of 680+, zero evictions in last 7 years.Class B Properties:Cashflow vs Appreciation: Typically, decent amount of relative rent & value appreciation.Vacancy Est: Historically 10%, 5% should be applied only if proper research done to support.Tenant Pool: Majority will have FICO scores of 620-680, some blemishes, but should have no evictions in last 5 yearsClass C Properties:Cashflow vs Appreciation: Typically, high cashflow and at the lower end of relative rent & value appreciation.

Examples include owning a single family and renting out a room, or owning a multi family property, living on one floor, and renting out the other

In addition, you have to fire suppress the home which typically costs around $40-$50,000, depending on the size of home.

This typically requires 125% of the mortgage debts in available assets. 

If you're buying as an owner occupant, your interest rate will be about 1% lower, so you'd be closer to 35% down.But with low risk real estate investments you typically have an appreciating asset, and high rent growth.But if you are buying with a VA loan with 0% down the reality is 100% leverage, it will take many years and interest rate drops to get to break even.

@Catherine Javier IRS Pub 527 states "Example.

I've included an example below to help illustrate this.So different lenders have different rates (which do vary even for DSCR loans) but these are factors they all consider.See example below:DSCR < 1Principal + Interest = $1,700Taxes = $350, Insurance = $100, Association Dues = $50Total PITIA = $2200Rent = $2000DSCR = Rent/PITIA = 2000/2200 = 0.91Since the DSCR is 0.91, we know the expenses are greater than the income of the property.DSCR >1Principal + Interest = $1,500Taxes = $250, Insurance = $100, Association Dues = $25Total PITIA = $1875 Rent = $2300DSCR = Rent/PITIA = 2300/1875 = 1.23DSCR lenders generally let you vest either individually or as an LLC.

A lender is not going to lose money on a deal for you to gain experienceYou will need to partner with someone to get experience and at the same time start savingTo answer the other question you typically will need 20-30% down to get hard money