location, amenities etc. that would make it worth more.

Its not worth wasting everyones time to put something into writing.

I think paying them is worth it if this is the case.

Because a verbal acceptance is not actually a thing, there was nothing worth rushing to convey to you and nothing that you could have done differently.

In my opinion, the BP books they have published are well worth their cost, so are the podcasts which are free. 

An LLC adds complexity and cost that may not worth it.

Imagine if your parents owned a property that was worth $500k and someone convinced them to sell it for $300k, how would that make you feel?  

There's no hype, no pressure, I don't do presentations where I print out all the low comps and try to tell them "Your house is only worth $X" In addition, I wholesale deals where my profit is less than a 3% commission.

I am looking at a property, that is worth about $130,000 to $150,000 depending on how much I end up putting to remodel the place.

Since the owner is rehabbing three of the four units, it should improve the worth of the property.