Six of the apartment were renovated with spray-foam.  

I guess because they were spraying and it was cheaper.

Matt:Salt air and spray are not friendly to composite roofs either.Lots of metal roofs here along here coast which are the better part of a century or more old.

Knockdown and spray finishes take care of 99% of your problems unless there is mold or water damage.  

Does anybody have a recommendation for a paint sprayer for spraying trim and windows with latex paint?

I spray all of my homes during rehab but I wouldn't think of spraying a finished house.

If the stove/oven is disgustingly dirty..I spray it with Heavy Duty Easy off ( sometimes I spray it 2 days in a row and then clean) and let it sit for a day or two..if the drip pans doesn't look clean enough that I would cook on it, then I just replace them.

When I was inspecting this unit one day, there was a puppy pad half way up the cabinet, with a urine spray where the dog lifted his leg.

It shouldn't really take more than a day or two for a single person to spray an entire house inside and out using an airless sprayer.  

I think ozone will be your best treatment, however you may need to hire someone that has commercial grade ozone equipment.If I were to do it over again I would ozone, spray probiotic cleaners and let sit for several days.