Plus now that I'm established and have a portfolio, I pay a lot into the local economy by hiring contractors, buying materials, etc.

Quote from @Cliff Song: Here's a metaphor.You: "What's the best flooring material for my in-home basketball court?"

Quote from @Devin James: @Jay Hinrichs Developments are definitely BIG money makers, but thats also reflected with the risk associated.That's why these projects take so much time and capital, but if you make the right judgements for project selection, and do all your due diligence, it'll turn out well. my 90 home project in Oregon  started it as dirt before covid .. got 1st phase built then covid hit.. had to fight through lumber sky rocketing and other material shortages and the of course interest rate spikes.. but the project ( and I give credit to my Wife and my GC's attention to detail) has sold Very well for record prices and profits .. its de risked now 22 lots left 13 are presold with big non refundable deposits and only 9 lots left that have no debt..

The chimney’s exterior, made of metal tubing, will remain intact.I plan to hire contractors for the entire project.

Generally, if it was due to sudden damage, the cost to bring the roof back to the same condition using the same materials is not a betterment.  

Furnishing a bedroom is very subjective but can be done for under $3K with higher than average materials.

Squeezing the architect costs to save a few thousand is pennies as compared to the hundreds of thousands coming by way of costs for construction (materials & labor), filing and inspection fees, etc.

Are materials and labor taxed differently?

Things like leaking pipe under sink, downspout that needs securing, sewer vent pipe out to the attic, missing smoke detectors in a unit, loose material, etc. are all very easy fixes that we would be happy to make for you. 

Even if there is a due diligence period, that is material information that should be provided up front.