As for environmental study, what is it for and why one bank asks for it and another one does not?

And all the other environmental and mechanical issues mentioned already. 

Secondly,  environmental issues.

We would appreciate any insight on the purchase process and financing connections we can get.Assumptions: 1) Credit score of all parties is 720 or higher. 2) For our due diligence, we are planning to have the following done:  a) An inspection  b)  A PCA (this includes an alta survey and an environmental study)3) We would like to put as little as possible down and obtain the longest amortization possible.  

In the meantime, read and study as much as you can about all aspects of this field.Any legitimate real estate transaction of any substance requires attorneys to review and create contracts and deeds etc, earnest deposit money, substantial due diligence money for appraisals, surveys, environmental assessments (phase1 etc) and inspections.

@Heather Fetter I think you're confusing building codes with environmental issues.

Show me a property anywhere (that is not covered by water or has environmental issues) that isn't worth more today than it was in 1965!

My name is Heather and I am looking into REI to help people have environmentally safe places to live.From 2007-2011, my family lived in a home with hidden toxic mold in the walls.

Anyway, here are generalities:EnvironmentalsSurveyTaxesInsuranceOccupancyUtilitiesLeasesRent RollRent comparisons against other complexesMEP's (including sewer/septic)RoofStructureWindowsCosmeticsAppliancesOF course, these will vary depending on the type of purchase, for example having an environmental report on a SF is not customary, however, it is on large MF. 

The city had told me to simply put holes in the bottom of the pool and cave it in,,,however the house is now vacant and a fence section fell down, now the city is involved in the house, the Environmental Department wants every bit of concrete removed when the pool is taken out (additional cost about $5k which I hadn't budgeted.If I decide to walk away because of this, the house will go into foreclosure, the city has told me they will go in and have the pool removed (and I'm sure they willl end up spending a lot more than I would),,and put a lien against it.Common sense would say they would come down a few thousand to help me with the cost they caused by taking over 2 months to give an approval,,but I doubt they will, the house will be vacant, the city will put a lien against it, and the bank will end up getting substancially less than they will if they sell to me, but thats probable what's going to happen (at the same time short sales can be super deals, if they work out)andy