Some studies say that people are approaching 40% of their gross for housing now in the US!

However your situation becomes a trickier case study since these properties first served as your primary residence which could provide additional benefits form a tax perspective not available to an owner of investment real estate and nobody has a crystal ball and knows the property with certainty will transition into an investment property. 

I am curious if the fees I am being presented are in line with market norms:lender app fee: $10,000Origination fee 1% ($20,000)Lender costs: shows a fixed amount at $10,000processing fee $895registration fee $10,000Title and escrow fees: $4,000 est.6.5% rate fixed at 10 yearsPrepayment Penalty: Yield Maintenance months 1-114 (1% minimum)Third Party ReportsApppraisal Required Engineering Required Environmental N/A Seismic Report N/A Market Study N/A Funded EscrowsReal Estate Taxes Required Prop/Liability Insurance Required Special Assessments N/A Ground Lease N/A Replacement Reserves N/A Required Repairs TBD Debt Service Reserve N/AWould love to hear your thoughts on this as well as what you think is appropriate fees for the freddie mac sbl program. 

Here is my expected cost:Land: $475kAcquisition Costs (Environmental, Survey, Geotech, Traffic Study): $25kSoft Costs (Engineering, architect, impact fees, permit, legal, closing costs, taxes, interim interest): $300kSite Development Costs: (Earthwork, underground utilities, curb cuts, fencing, stormwater, paving, landscaping): $800k ($400k/acre)Subtotal before vertical costs: $1,600,000 ($80/SF). 

I realize there's no way to capture everything, and learning is a continual process, but it feels helpful to me to have a working "cheat sheet" of information to study and reinforce important concepts.

Hi Andrew don't expect a perfection first step is to study carefully everything. 

I'd study the John Martinez stuff out there. 

You can actually start studying before you are 18 so that you are ready to take and pass the test soon after you have your birthday.My guess is that at 18 it will not be easy, but don't let that stop you. 

Use Furnished Finder to study comps, and talk to some local property managers to see if they can help you get an idea.Once you have the gross income potential number, take that and back out all of your expenses.

Study the market.