Here are the details:Relinquished Property Sale Price = $310,000Closing Costs = $25,000Mortgage Payoff = $35,000So, after the two transaction costs listed above, we'll walk away with $250,000 deposited into the QI fund.That would be 1/3 of the new property cost, roughly equivalent to the value of the investment portion...or does the investment portion need to be equivalent to the actual sale price of the relinquished property--in this case, $310,000?

Having rental history via a schedule E in your tax returns would help, but an executed lease agreement and proof of security deposit and/or rental income received should suffice. 

Price should almost always match condition and location when it sells.

Think of all the things that could go wrong and see if the lease addresses them: unauthorized pets or tenants, early termination, security deposit, lease violations, late rent, eviction, lawn maintenance, parking, etc.5.

Do you require an application or due diligence deposit? 

I was all set to do a cash purchase and the owner of as having his lawyer write up a contract for the deposit.

He has signed the lease and has initiated ACH payment for first month rent and security deposit.

Rehab should force appreciation, but sometimes your opinion on value doesn't match the appraisers opinion.

Blue Spot Home Loans - They said they'd consider, “future rental income” if you secure a lease agreement AND security deposit for rental of your existing condo prior to final loan approval for the condo you will be purchasing. 

Here's what we do (copied from our website):Screening ApplicantsPoor screening often results in lost rents, legal & court costs and costly damages.Screening of applicants includes the following:Full credit/eviction/criminal checks are done, instead of score-driven reportsVerification of rental history includes validation of actual property owner to avoid fraudVerification of stability of income & employment via YTD paystubs & W-2(s) (analyzed to confirm not fakes)Income is calculated 3 ways to spot stability anomalies: pay period, YTD average and YTD + W-2 average.Debt-to-income analysis (more accurate than traditional 3x rent requirement)Bank statement to see if NSF issues, if deposits support income, prove MoveIn Funds, also analyzed for unusual transactions.Pet screeningHolding Fee required from approved applicants to make sure they are serious, before your property is marked pending.