A home has been on the market for over 426 days, what percentage is best to bid to guarantee a win

I know renters warehouse offers to find tenants as a separate service, I only used them once, my only out of state property, it was expensive but “guaranteed”. (1.5 months for a 3 year lease.)

Nevertheless, the co-signing usually guarantees a better outcome.

Everyone does.Using a licensed and insured contractor is nice to have but doesn't guarantee quality workmanship.

Right now I cash flow $770 a month if everything goes well but If took the money I could lower my mortgage payment by $450 (pay off land loan for primary resident) and a big chunk of my LOC that I owe and that is guaranteed so its like im really only cash flowing $320 since I always take that money to help pay for my mortgage.

As @Marc Winter mentioned, you should already have the first month's rent as additional collateral.I do not sign the lease and cease marketing until all move-in fees are collected in guaranteed funds. 

@Connie Steele - If you're signing a personal guarantee (recourse loan) then the bank wants to continually verify your ability to repay the loan. 

When you add value to multifamily, it's almost a guarantee that there will be a drop in occupancy initially as you evict the non-paying tenants, and as you raise rents folks will move out.

Some are obvious and get no bids but often at the auction, you will hear a property end at 14 or 15 or something and there will be a tittering of chuckling in the crowd because they know some idiot newbie thinks he just invested his money at a guaranteed 14% but in reality, just tossed away his cash on one of these zombie PINs.Now it isn't all bad, there are plenty (better to say some)  of decent PINs which don't get bid to Zero and they get redeemed, or I assume some don't redeem and are good.

@Joe Villeneuve Joe, I dont understand this "Guaranteed Rent also known as Rent to Rent is where an individual or company takes an interest in a property for a period of time from a landlord and guarantees to pay a fixed rent to the landlord.