Now knowing that this property is under a leasehold agreement how does this effect the value of the property?

It like most other things in investing you must learn all about to use it effectively.

Maintenance is another question - what is the effective age of the property?

Most sellers would not have the ability to report to a credit bureau, so it probably wouldn't have any effect. 

I suggested writing into the Offers that each offer is contingent upon the other, or something to that effect.  

Efficiently and effectively manage my three-unit so that it generates $200 cash flow per unit per month.3.

Hey BP, This is a "One Thing" type question that I'm asking to help me focus my efforts on only the most effective actions.I do bandit signs, door knocking and cold calling....Is there anyone who has found success with a small starting budget that can share what activities they found to be the best use of their time, in terms of deal generation?

Very simple yet very effective means of redirecting the water out of the basement.

How it usually effect in real estate in Houston?

For rental purposed you should stick with Goodman or Ducane as they are cost effective.