Frank's back of napkin analysis would generally include that expense. 

Is there a back-of-the-napkin calculation for insurance quotes for small (2-4) multifamily properties?

Also, water and wastewater plumbing, specially sanitary will be an issue. 

I also didn't see any soft costs like civil engineering, architecture, MEPs, etc.Happy to sit down and talk more precise numbers instead of back of the napkin estimates or help in any way I can =)

Also, snow removal, if you live in a climate with snow and ice.Landlord Responsibilities: Landlord will at all times during the tenancy keep the premises fit for human habitation, and shall in particular:a.Cultivate, care for and mow surrounding grass, lawn, flowers, and shrubberyb.Maintain the premises to substantially comply with any applicable code, statue, ordinance, or regulation governing the premisec.Maintain the roof, floors, walls, chimneys, fireplaces, foundations, and all other structural components in reasonable good repair as to be usable and capable of resisting normal loadsd.Keep any shared or common areas reasonable clean, sanitary, and safe from defects increasing the hazards of fire or accidente.Provide a reasonable program for the control of infestation by insects, rodents, and other pests at move in f.Except where the condition is attributable to normal wear and tear, make repairs and arrangements necessary to put and keep the premises in as good condition as at move ing.Provide reasonably adequate locks and provide keys to the tenanth.Maintain all electrical, plumbing (main lines), heating, and other facilities and appliances supplied by Landlord in reasonably good working orderi.Maintain the unit in reasonably weather tight conditionj.Provide facilities adequate to supply heat and water and hot water as reasonably required by the tenant

If the sanitary conditions in your unit are such that it attracts pests of any kind, and it becomes necessary for us to undergo remediation in the building, you will be held financially responsible for reasonable costs thereof, paid as additional rent.I think you resolve this with the tenant by attempting to negotiate them paying, but if they push back you may just have to eat the cost as tuition since your lease is silent on the issue.

Call that guy and offer them $100 for an hour walk through with a back of napkin bid that he can confidently call a price with a 5% margin of error. 

The remaining 50% ($1,000) will pay the mortgage ($800) which leaves you $200 a month in cash flow.That's a simple way of looking at it on a napkin.

You can do some back of the napkin calculations to determine what the costs would be and what the potential revenues would be. 

Most likely you can write "I agree to pay $260,000 for the property at 123 Ontario Lane" on a cocktail napkin and send it to a title company and your bank.They will guide you through the rest.