I can really only speak for California but I tend to avoid anything older that June 15, 1976 for a variety of reasons from safety, quality of construction, finance ability, resale, etc.

Sorry for some reality in real estate contracts, if you want a contract to hold water there MUST be a financially measurable consideration given as you take an equity position at the time you contract, no money, no equity!

I would recommend measuring your risk aversion and talking with a local attorney to better understand the two options available to you.

Write down your goals as they should be measurable.  

I would not do daily visits to collect rent because that situation could get ugly -- don't jeopardize your safety and sanity.If you don't get October rent give PQ notice and start eviction.

(there was a insulation measuring guide by attic entrance, this makes me think this was recently added)*crawl space also had new foam insulation and looked very nice,  found some mold (yellow fuzzy) on one beam but inspector said it was most likely from before it was redone and could be cleaned up fairly easy since it was not in a living space. 

OH yes I get 7 to 10% on my notes and they are collateralized by rental houses.. so the DCR is insane its 2 to 3X  and two forms of repayment.. one tenant two the owner.not to mention owner has put 35 to 50% CASH down ... now it simply does not get safer than that. 600 notes in last 3.5 years total of 3 defaults which were quickly cured... talk about safety..

Oh got it, thanks so much @Calvin Kwan I know Oakland residents are also voting on a measure today that could drastically change the composition of folks on the rental board https://oaklandnorth.net/2016/10/28/oakland-residents-to-vote-on-rent-control-initiative-this-november/

I bought "What Every Real Estate Investor Needs to Know About Cash Flow ...and 36 other key financial measures" by Frank Gallinelli.  

@Jacob Eddy, there are several ways to measure how good a deal is.