There is no magic formula that can fit any and all investors.My advice is start with one or two (houses, condos or 1-4 units building) see how it goes, how you like it.

Sometimes in OC ARV formulas go out the window and investors will pay way more than you think.

@Kevin Keene , Here are my thoughts:First off, you should definitely NOT be relying at all on Zestimate for values.Secondly, it took me a bit to figure out what you were doing with the ARV calculator formula.  

Success is not a straight line formula.

@Kirk Rohani,If you plan on rehabbing and selling it, here is the formula that most rehabbers use:ARV minus 30%, minus the repairs, equals the max price you should pay.$240K minus 30% = $168K, minus $35K repairs = $133K.Because you plan on not using a Realtor to sell the house, you can add 5-6% to your purchase price. $240K minus 24% equals $182K, minus $35K repairs, equals $147KAs a rental Property that rents for $1500 per month, the final price should not be more than $150K.Some landlords are happy with 1% of the purchase price, and others won't settle for less than 2% of the purchase price, for the Monthly rent.Raymond

There is not formula to produce an accurate figure because it all depends on revenue and expense correct?

Without seeing how your formulas are calculated, I can't tell you where you're going wrong. 

Most will say 'no' but just keep at it.The basic offer formula is 70% ARV (after repair value) minus repairs minus your fee.

I've read here and heard elsewhere that with seller financing, the TERMS are where it's at and not necessarily price so I don't want to "price myself out" of this with the traditional wholesale formula if truly there is money to be made with a different, yet financially workable approach for all involved.What questions should I ask and what should I be listening for?  

Do you compare the property with other properties in the area, or do you use a formula?