Say 220 was roofing ststems for expenses, 221 could be felt, 222, shingles, 223, hardware (nails, screws, trim, drip trim, vents, sofit) 224, decking/lumber, 225, roll roofing (including rubber systems) 226, glue/adhesives...you get the idea.If you are knocking out say 4 basic floor plans, different elevation but all the same materials/grades, you are buying bulk and allocating costs based on the plans per plan.

There are better sources for conventional educational materials with college and vo-tech courses that are more applicable to you than RE agent/broker paths.

I'm not going to get specific because these are often driven by individual facts and circumstances.

Generally I have a policy of saying no to all tenant requests but will agree to some if the tenant pays and I have all final say on materials and finish.

“Drug-related illegal activity” means the illegal manufacture, sale, distribution, purchase, USE, or possession with intent to manufacture, sell distribute, or USE of a controlled substance (as defined in Section 102 or the Controlled Substance Act (21 U.S.C. 8002) or possession of drug paraphernalia.2.Resident, any member of the resident’s household or guest or other person under the resident’s control shall not engage in any act intended to facilitate illegal activity, including drug-related illegal activity, on or near the said premises.3.Resident or members of the household will not permit the dwelling to be used for, or to facilitate illegal activity, including drug-related illegal activity, regardless of whether the individual engaging in such activity is a member of the household.4.Resident or members of the household will not engage in the manufacture, sale or distribution of illegal drugs at any locations, whether on or near the dwelling unit premises, or otherwise.5.Resident, any members of the resident’s household, or a guest or other person under the resident’s control shall not engage in acts of violence, or threats of violence, including but not limited to the unlawful discharge of firearms, prostitution, criminal street gang activity, intimidation, or any other breach of the housing agreement that the other wise jeopardizes the health safety or welfare of the landlord, his agents, or tenants.6.VIOLATION OF THE ABOVE PROVISIONS SHALL BE A MATERIAL VIOLATION OF THE HOUSING AGREEMENT AND GOOD CAUSE FOR TEMINATION OF TENANCY.

This assumes it's $10k worth of rehab, not just materials, and you include labor costs...What investors do is buy the house for deep discount to what it's worth at $80k, add the $10k in repairs and get the appraised value up to $110k. 

You can only charge what you have been charged, so if you do the work yourself, you can only charge for materials.

I'm curious to what materials YOU use and where do you usually buy them from?

I'm not saying that price drops will 100% be driven by interest rate hikes but I think interest rate hikes are more certain (in the near term) than a housing crash.  

Feeling good that one day I hope to get out of my dead end job I have a storage unit built into a house that I have all my materials in which I had nothing into.