When I sell my business I will have 300k to invest puss 300-400k left over after I buy my residential house.

Deduct NEW property taxes after you buyDeduct home insurance costsDeduct maintenance percentage, typically 10%Deduct vacancy+tenant nonperformance percentage(we recommend 5% for Class A, 10% Class B, 20% Class C, good luck with Class D)Deduct whatever dollar/percentage of cashflow you wantNow, what you have left over is the amount for debt service.Enter it into a mortgage calculator, with current interest rate for an investment property, to determine your maximum mortgage amount.Divide the mortgage amount by either 75% or 80%, depending on the required down payment percentage - this is your tentative price to offer.If the property needs repairs, you'll want to deduct 110%-120% of the estimated repairs from this amount.Be sure to also research the ARV and make sure it's 10-20% higher than your tentative purchase price.As long as the ARV checks out, this is the purchase price to offer.It is probably significantly below the asking price.

Not to mention you need to have some liquidity left over after the deal closes in order to qualify for a loan. 

.: Quote from @Theo Hicks: In ideal conditions:Pref equity receives higher ongoing distributions but no profits at saleCommon equity receives lower distribution and profit at sale (assuming their is cash flow left over after pref equity is paid and assuming their is profit at sale.In non-ideal conditionsPref equity may receive ongoing distributions less than pref, or no ongoing distributions at all, but the pref accrues.

That's enough to pay off the original loan and pull the $85k you had in rehab costs, with a little left over to cover your closing costs for the refi. 

The reason I say off market is because most seasoned real estate investors do not want to buy someone else's investment flip and if the property is a deal such as the ones you are looking for, it will likely sell quickly, which leaves you with the leftover inventory unless you're ready to make a quick decision every time.

Anything leftover goes to homeowner. 

I can count the number of those people who were healthy and happy on one hand, and have fingers left over.

They spend a ton of money on advertising their product and apparently have none left over to spend on product development.

Total of 5,000 seedlings, plus left overs from last year and ones we bagged and seeded ourselves.