I am trying to get estimates from reputable contractors to redo the stucco on one of my investment duplexes in San Diego.

Why would an agent not present your offer, risking losing their license, listings, reputation?

Check with your local housing office in charge of titling manufactured homes.

And in section F-908.7.5 it stated that owner of the building (landlord) shall post a notice in common area and inform tenants about CO alarms and provide with manufacturer instructions.

Its an embarrassment to the industry and they should be run out or fined for attempting to knowingly sell unsafe properties to unsuspecting consumers.Property inspectors are not always the best group either, but in this instance they discovered some real problems it sounds like...that's what they are paid to do...It's always best to do things right...it's your reputation on the line. 

why not just use a reputable hard money lender that understands the business and is willing to take the risk along with you rather than looking for someone who doesn't know you.

I would recommend finding a reputable yet smaller property management company in your area to manage for you. 

Any and all suggestions would be greatly appreciated, including who not to use if there are people with bad reputations in the investor network.  

Pat has been managing other peoples properties for many years and as far as I know carries a good reputation.

The biggest portion of the field seems to be marketing and developing reputable motivated buyers.