Bigger Pockets can't stop sponsors from going on other sites (podcasts).

It's not perfect, but I like to read the reviews from residents on the site 

Does anyone have any tips on the best way to finance renovations/improvements for properties like this?

This is what I did for a cabin I built in Gatlinburg:  We took a few royalty-free photos of the area off of the internet, and submitted them to an art site online whereby they make a painting of the photo.  

Maybe do it officially for good measure.

It will give lots of tips to find the right syndicator. 

Besides land, infrastructure/site work, and the building construction itself, am I missing any other major category of costs?

While the housing market nationwide remains neutral, Atlanta joined a growing list of large Southern metro areas that have tipped in favor of buyers.

I watched my parents flip houses since I was little and have always been on job sites or made "pocket money" by doing chores like painting fences or washing kitchen cabinets, which I realize now my parents were putting us to work to build that sweat equity.

At the end of the day vet these lead gen sites/companies on a short-term basis, then flip to something else if the leads are not working while having the right expectations.