For Multifamily, here is how I break down my underwriting pro-forma and the expense cost rules of thumb I use:Annual Income:+Gross Potential Rents (Market Rate x Units x 12 months)- Concessions (depends on the market, but I try to limit to 3% GPR)- Economic Vacancy (physical vacancy + bad debt + loss to lease)= Total Rental Income+ Utility Income (based on past RUBs history or the per door flat fees)+ Other Income Items (Laundry, revenue share contracts, late fees, app fees, etc.)= Total IncomeAnnual Expenses:+ RE Taxes (usually use 3% increase over last tax bill, but make sure your area won't reassess immediately upon the sale at the new price, which could drastically increase the taxes)+ Insurance (my rate is about $200/door....yours will be different, talk to your agent)+ Management Fee (3-5% depending on size and company used)+ Administrative costs ($150/door)+ Payroll ($900/door, but the smaller the complex, the higher this cost usually goes)+ Marketing ($125/door, again it depends on the property size and market)+ Utilities (usually do a 3-4% increase over the past 12 month total)+ Repairs/Turns/Contract Services/any maintenance (depends on the age, I buy late 60's to early 70's vintage stuff and usually spend $750-800/unit....this goes down as the property is newer or renovated)+ Reserves (this will depend on your financing, but I place it above the NOI line here because if the bank requires it, it is an upfront expense monthly....usually $250-350/door)= Total ExpensesNOI = Total Income - Total ExpensesThis generally works well for properties 20+, but might not work so well for smaller complexes.

I've searched alot of homes on MLS in the 30-50k, and the compensation is outlined as either a percentage (usually 2.5-3% each) or a flat amount.As the BUYER, you won't typically pay your agents commission anyway.  

People that live in the flat lands have no clue how off the charts great it is on the east slope of the Cascades  they just don't.

I believe property managers usually take 10% of the gross and any expenses  or vacancy fillings are extra; how did you negotiate them receiving a flat rate for all repairs, maintenance and insurance?

If you never find one that's Florida specific you could post a CL ad and ask for a RE law student who can review the documents that you are unsure of for a flat fee of 50 bucks or whatever you can afford.Just an idea!

Flat is cheaper otherwise....  

Do you just make the down payment a percentage of that or a flat amount?

I have to agree with @Johnson H. that there's a high probability that the market will stay relatively flat to single digit movement in the near future.  

For Multifamily, here is how I break down my underwriting pro-forma and the expense cost rules of thumb I use:Annual Income:+Gross Potential Rents (Market Rate x Units x 12 months)- Concessions (depends on the market, but I try to limit to 3% GPR)- Economic Vacancy (physical vacancy + bad debt + loss to lease)= Total Rental Income+ Utility Income (based on past RUBs history or the per door flat fees)+ Other Income Items (Laundry, revenue share contracts, late fees, app fees, etc.)= Total IncomeAnnual Expenses:+ RE Taxes (usually use 3% increase over last tax bill, but make sure your area won't reassess immediately upon the sale at the new price, which could drastically increase the taxes)+ Insurance (my rate is about $200/door....yours will be different, talk to your agent)+ Management Fee (3-5% depending on size and company used)+ Administrative costs ($150/door)+ Payroll ($900/door, but the smaller the complex, the higher this cost usually goes)+ Marketing ($125/door, again it depends on the property size and market)+ Utilities (usually do a 3-4% increase over the past 12 month total)+ Repairs/Turns/Contract Services/any maintenance (depends on the age, I buy late 60's to early 70's vintage stuff and usually spend $750-800/unit....this goes down as the property is newer or renovated)+ Reserves (this will depend on your financing, but I place it above the NOI line here because if the bank requires it, it is an upfront expense monthly....usually $250-350/door)= Total ExpensesNOI = Total Income - Total ExpensesThis generally works well for properties 20+, but might not work so well for smaller complexes.

Assume prices will be flat.1) Paying too much for the landThis can be mitigated a little by dialing back on the finish outs, but be careful you don't under build for your market.