You can easily get audited and caught for mortgage fraud for putting in a 12 month lease.  

They usually source it to a company that specializes in this area and offers audit defense if the client is ever questioned and at no cost.

I need to prepare for tax filing and potential audits, but I'm unsure if receipts for every expense are necessary.I had an incident where the PM mentioned a referral fee of $350 for a tenant, but the bill showed $400.

Many do not qualify and having a PM does not help your case.You may want to read up on IRC 469 and review the IRS's Audit Technique guide. https://www.irs.gov/pub/irs-mssp/pal.pdf

IT was a guy who was a sailor of some kind I believe, and he had witnesses attest to his hard work that allowed him to challenge the audit result successfully.

With this method, we can be confident that our conclusions are based on thorough research and impartial analysis.

One might ask if brokerage managers and transaction coordinators are performing enough oversight and auditing of the new, rookie agent’s transactions, AND communications with clients. 

Not a CPA or tax professional.I’ve never audited every single line item of my S-Corp tax returns for over 18 years, and I’m truly curious why it really matters in one years instance, what corporate account was used to conduct business, as long as the financial information is accurate and correctly reported from said dedicated business account.This should be a separate issue from proper and legally correct business operations, ie a checking account with correct tax ID, no outside commingling of funds with self or other business entity.

I HIGHLY recommend paying for a CFO audit & having them set you up first. 

I got audited for 3 years. all of the above was thrown out.One example I had a business trip to London then to Tel Aviv.