Because you are looking to operate a mid term rental, you actually have a bigger net to cast as most restrictions are specifically for STR's.

Zillow and Rent Cast are good for looking at Rent comps and BP has a rent calculator as well. 

I am just casting a net here.

Is the easement wide enough to have cast off that stays within the easement ??

If your just casting a net and hope to catch something, you can go lower and wait

Sometimes you can tell because of rust staining and buildup on the outside of such affected pipes,   but even without that they can be weakened considerably from their original state.On the drain side galvanized branch drains  (1.25 through 2" galvanized pipes)  can also rust out or clog up as the rust on the inside is very rough and catches hair, grease,  and other debris and will eventually need aggressive rootering,   which if the pipes have rusted enough may open up holes in them.I should note CAST IRON (hub and bell) old sewer pipe,  at least the 3" and 4" stuff seems to have a bit longer lifespan than galvanized steel;  it still rusts but doesn't crumble and flake and encourage blockages like steel does,   so an old house with a cast 4" sewer stack you may be fine for many decades more if you just replace all the branch lines going into it but leave the main stack.   

I listen to the wholesaleinc pod cast and they provide great information.

I listen to several real estate POD casts and i'v never heard of anyone talk about this topic which it seems (at least to me) to be an extremely important topic.business

The common theme here in BP is ... all the info you need is here for free, which it is.For some people who works 40 + hours per week and wants to get out of that  9-5 asap, they may not want to take the time to sift through all threads, pod casts and such, these courses may be a more time efficient way plus from what I seen they off money back Guarantees.

Seller Leads are a tough nut to crack, online they mostly come from Home Valuation ads, and as you've discovered they cast a very wide net and will find a lot of folks just wanting to know their home's value (who wouldn't?!).