We don't keep a ton of money in checking or savings and in turn aggressively pay down debt when we can while I also do fairly high payroll deductions for 401k and stock purchase plan.

If it's someone on their payroll and they didn't get invoiced, ask about their costs. 

Approaching people to find that small dollar amount is easier than you think because many people with smaller balances are less sophisticated investors and are excited about lending on Real Estate with equity.

Some of this is dictated by the sophistication of the sponsor, and some by the needs of the money.

We are fully licensed, fully insured, we have all of our workers on our payroll, company vans, trucks, and all of our own tools.   

If a property ends up on LoopNet in a good market, that property almost guaranteed has already been sent to a handful of sophisticated buyers who passed on the deal.

That would NEVER fly here, and any landlord who suggested it in small town New Hampshire would be a laughingstock, if not considered an outright creep.But matching rent payments to payrolls is common.

I see too you're in commercial, all the better reason to have a more sophisticated contract.

I have read some books and surfed online about money and investing etc but it all makes my head spin as it has gotten so much more sophisticated and uncertain.

Even in the institutional side of loans, depending on the sophistication of the investor holding the loan, things can be done incorrectly, like servicing and accounting, etc.