In most cases, here are some universal tips :buy for cashflowbuy value-add as it helps insulate risk as a newbiebuild a team in areas you are weak in or do not want to docheap multifamily will typically rent to low income tenantscheap multifamily will have bigger renovation budgetscheaper price fees and large unit count portfolio's do not equal a good property managernever assume anythingpartner upand if raising capital, raise early as @Taylor L. so equivocally mentioned. 

Just make sure whoever installs them insulates and caulks them correctly.

Adding some value put in insulation this weekend, putting up gutters and some other stuff.2.

I use cellulose insulation blown into the joists space in the ceilings of the basement unit.

I just put in $20,000 new sliding, $5,000 new electric box and wirings, carpet, water heater, new paints, new fridge, new vapor barrier and insulations.

Then they will inspect framing, insulation/Vapor barrier , amp final inspection.

The "upholstered headboards" are insulation board covered in fabric.

Then insulation, then drywall, then paint primer.

Reduce operating expenses, particularly heat and water (new windows and insulating the building better should help with energy costs, it seems the previous owners have invested $0 in this).

Any ways, current code requires 6x2 on exterior walls to allow for the correct amount of insulation.