Nevertheless, if the RAD investors  actually had loans  collateralized against property they would be in a much better position.

No, they don't find my properties. 

(FWIW,$8K on just the compressor seem excessive.)Otherwise, unless your contract with your GC says they will provide 24/7 surveillance, or you can prove the AC was never installed, you own the problem.If the property has been vacant for more than 30 days, most policies won't cover vandalism unless you have added a Builders Risk Addendum.

Purchase price: $420,000 Cash invested: $120,000 5 bedroom 2 bath property with pool, shed and playground in the backyard.

This is a great look cost preventative maintenance thing It also allows you to "inspect" your property periodically

Property values soared high in this town since past 7 years.

Has anyone added extra bedrooms to a multi-family property to increase rental income?

Hard to say much without seeing the property.

If not, consider a 1031 exchange when you sell to defer taxes on profits.Texas is a great market, Id hold that property for as long as you can! 

Let's say I want too go out and network where would I find investors and lender's that can help with the first down payment on a property and is there any events that has REI and CREI.