This is where one needs to start looking at Purchase price / rents   and come up with a formula they are comfortable with.. 

Weather it’s 30% 40 or 50 , it’s important for you to be comfortable and to save At the same time however ,    you must be a very experienced investor if you’re making 30 K each month from your investments so I would imagine you have a successful formula .            

Value adds for years to come with seasoned investors with comps to get ARV's easily (and follow the formulas). 

Thanks Jon--It's a flip--same one you counseled on concerning ARV formula and cheap money on an earlier thread---bank took it off MLS and now it's listed with another realtor.

I have 2 investors that I've peaked interest with, but I want to make sure I'm doing my numbers right and not missing something.Does anybody have a good formula for doing an income valuation approach on the parks/parcels that are owned.

Once the inspection is complete and it passed, the case agent will call you and ask if you will accept a certain amount, which is based on an income formula. 

I'm looking to hear them :) in all the direct marketing approaches no one seems to be laying out how much it is they are offering or their "magic numbers or formulas."

The formula is there.

Implied in that is that the formula should attempt to be fair.  

My expertise is limited to Self Storage and I'd be happy to share a few of the formulas that I use to valuate them if that's an area that you are interested in.