What everyone needs are products, services and policy structures designed by real estate investors, for real estate investors and one of those features is a portfolio type master policy, with no location limits, with the ability to insure multiple controlling entities and properties in any stage of renovation, in all 50 states, offering agreed value, special form coverage with theft and vandalism, the ability to actually reduce premiums incrementally by aggregating locations AND do it all on a monthly reporting basis so that you and your CPA can easily see the breakdown in coverage and premium for every location. 

They force you to constantly do specials that reduce your profit margins.

For example, city of Austin has some rediculous energy efficiency requirements as well as ever-changing codes that take effect on properties with an ownership change regardless of how old the building is. 

Yes, those starting out, and beyond, who are self employed look for every expenses they can, some exaggerate and that reduces your ability to borrow.

If there is a slip and fall claim made by a biz customer, the tenant biz policy will defend you, greatly reducing the likelihood that your policy would pay any part of the liability claim.   

A lot of investors and wholesalers put a lot of energy into doing volume...40+ deals a month.

Loving the energy here.

It's been producing a LOT of carbon monoxide, so much that I feel like it's a hazard to go into the basement to work on it.Does anyone have any ideas about how I can 1) reduce the amount of carbon monoxide produced or 2) better mitigate?

Be sure and do proper screening to help reduce chances of getting a bad tenant.

If they have a 15 page check list you already know what you are up against.If you haven't bought the property yet can you schedule an inspection with them and use the report as leverage to get the price reduced?