I'm working to determine the cost of building a modular home.

I recieved a interesting deal from a whole sellers. Asking price is 225k, 12k to demo the currently building, although it can be renovated. Arv for 3,000 square foot home 500k. I reached out to a modular home builder for an estimate. However they have yet to respond. Can someone please help me with the cost of the new construction?

@Lamar Allen , take this for what it is:  I have priced out new construction with a builder on a couple lots.  A friend that used to be a builder once told me: asking what it costs to build a house is like asking what it costs to buy a car?  I sold my college car on craigslist for $500.  I could walk into the Bentley dealership and spend $300k.  

For a very rough estimate, I was getting about $150/psf to build new, not including the land.  I am not a GC with new construction experience, so typically the new construction is handled by builders, since they are making their GC fee and any profit.  You, looking to hire a builder, will be paying their GC fee, which can be 20-25% of the total cost.

There are a million variables though.  How much of 3,000 sq ft is above grade versus below grade?  Below grade sq ft are less expensive than above grade.  Front doors can be $200 for the bargain basement sale rack or $5,000 for a high end 8ft tall double door.  Windows can range $250 installed for basic double hung and up.  Tile can be $1psf to $50psf... and on and on.  

Generally, it is always going to be cheaper to rehab than build new. But in my market, generally, a rehabbed ARV will be 15-20% less than new construction. So the additional cost of new might end up being worth it.

I have worked with modular builders to build ADUs and some homes.  I think you can make it easier for them to answer if:

• You reference a model they have already built in the past
• You exclude site, land, permit, utilities, kitchen appliance costs (you can shop around to find the sitework person yourself) 
• You are only getting the most basic options (you can always shop around for that)

If they can't give you an answer with those, I would avoid them at all costs.