I read online that a rent increase of 10% or more requires a 60-day written notice.

The properties I feel that have some value-add are the ones that a bank wouldn't lend on, such as a property where leases are coming up and I have opportunity to increase, etc.

....There are many factors that play into this obviously such as pay increases at my job, getting married etc. 

This is especially important if your decision to be hands-on (ie self-manage, handle maintenance repairs yourself) is motivated by the desire to increase returns by cutting out the middle-men.

@Jon Paszkiewicz, I might be confused: Why does buying the two SFR's increase your starting cash pile?

The prices have increased over the years and it has become very competitive but there are still deals to be found.

With continued increase in interest rates, Cap rats compression will slow down in the hot premium markets. and are likely to rise in most other markets. 

In other words you receive a 30% tax credit on the solar system as well as a 30% tax credit at the least on the roof that is under the solar system (full roof 30% depends on the advice of your CPA).Couple that with the roof now becoming a producing asset and offsetting the utility bill instead of a liability and the increase in appraised home value assuming the solar system is not leased then going solar makes a lot of sense at the same time as replacing/repairing a roof.So in short you don't "get a roof if you go solar", but there are certainly advantages to adding solar to a roof replacement.

Based on my experience, you should increase Repair expense and Cap X expense to at least $100/each per month ( I would be more comfortable with $150/each per month).4.

You might feel that they deserve some interest on the loan but you might not be able to deduct it.If you do not care about it's ability to make money or an increase in value over any time.