Unfortunately - my current lot for my primary is 1 acre and VERY sloped, and close to a water source (creek), so the county has not even allowed me to permit my downstairs finished basement without an extremely costly renovation to our septic (over $60,000, and that doesn't count demo'ing and replacing our driveway to get to the existing tank and leachfield), and even if I could permit it, it would essentially need to be a treehouse in the redwoods due to the slope (not a bad idea though, I would actually love a livable treehouse on this lot!

I've tried a couple - truepeoplesearch, white-ages, property radar, leadsherpa, batch leads...Some services are better than others, but it is a numbers game and you also can cross check between different platforms.

I am hoping to be in SWFL to inspect the final product by June, fingers crossed...

Typically, the adjustments I see on appraisals for basements are more flat rate adjustments. 10k is usually the number I've seen.What stinks is that there are a couple of model types that have below grade space where the builder, I'm sure, was trying to lower the taxes by having it below grade so the county wouldn't count that space in the assessment.

Brewerytown and East Passyunk could also be worth exploring.Big projects like Bellwether can boost neighborhoods, but they often take time to show results, so don’t count on them as a main factor.

For the multi-family, lenders typically count about 75% of projected rental income toward your debt-to-income ratio, which should help if the property is cash-flowing.

When in Doubt for Florida, look them up on Sunbiz.org, search by Company name, then cross reference with owner name.You go deeper and check Civil Records for Lawsuits. 

Oh yes and selling to yourself does not count as selling, even if you match highest bidder.

I also listed properties that were supposed to cross list to Zillow/Trulia but would not show up. 

If the value of a $700k house goes to 1.2M over the next 10-12 years, you just turned $50k into $500k (not counting loan paydown and cash flow that would come over time).