Account Closed on your question.Years ago, I made the mistake of forgoing quality for quantity, which led to headaches and a fundamental change in the way our company operated and in the way I personally invested.

Great discounts usually happen when large quantities of real estate assets default and become bank owned.

I think the Average for a 1040 is like $400-500 - so keep in mind that's an average that includes big cities, and also what people are charging in tiny towns. 

On a bigger job it makes more sense to do the $1,000 deposit then make sure they mobilize properly and have material quantity on site then release a material payment.

I already have land w infrastructure going in for another venture and thinking about the tiny house rental on it for a temp light cash making but if you search VRBO/AirbNb for comps you’ll see they aren’t heavy cash makers, mostly due to the smaller season.  

You can also find places online that will deliver slabs but I haven't done that yet and I only found one that seems to do small quantities. 

I won't speculate upon repair costs because I don't have a clue about the quantity and quality of materials as well as your local labor rates.

On the east coast, we buy in quantity for our apartments from surplus warehouse and get a discount from the normal $1.50 +/- regular pricing.

Jason, depending on how much dirt you need quantity wise, I'd recommend using clay based soil.

Be ready for a list of deferred maintenance though,  when people pay tiny amounts, they won't  tell the landlord about anything because they fear rent increasing- but when they are paying more (even below market rate), they want stuff fixed that they overlooked for likely years.