This is probably not the last law they will pass to marginalize the "rich landlords" in the pacific NW.

In my experience, the first loan will be variable and fluctuate with prime (libor) plus margin.   

The return is so marginal using your calculations and as Justin R indicated the investment needs to be compared to other available options. 

If I was looking at it to build a spec house  70k all in is about right for a 350k exit  120 way too high.100k if your very efficient builder.. or a owner / builder and gets great pricing.. 4X is kind of a rule those price points.were it flip flops is the   2 million dollar lot and the 8k build and sell for 4 million like I am sure there is stuff in seattle like that and bay area and other high priced areas.but at the 350 exit I like the 1/4 or less for lot price to make a 15% gross profit margin after all costs.

The margins are stripped off a lot of those deals since the local flippers are often very willing to pay a premium just to get a deal locked down, so keep that in mind. 

So if they only held quality properties they would have done very well no matter the cycle but the marginal to losers were wrecking the returns on the overall portfolio.     

I think the reason a lot of investors go high end in single family homes could be because you only have one unit, so the profit margins are squeezed, in order to turn a nice profit, you must command higher rents.

I should also note that I do have my real estate license, but I honestly don't have the time to use it, but man, I would save a lot of money if I did :D Target Profit Margin $18,000Actual Profit Margin $17,500Financing used: 80% of home and renovations covered by bank with an interest only construction loan.

. % does not work.in our production stuff like we do in Oregon  were the end product is now in the 450 to 500k range  1/4 to 1/5 is what you need for land cost to keep your margin at 15% of gross or there abouts.. but many builders are only making 5 to 10% of gross if that , depending on where they get their construction money.our Gresham project Lennar offered me 130k per finished lot  and we are selling houses right at 450k.. so they were paying top dollar but they build 400 plus houses a year in this market so their margins are much tighter and they are not carrying ANY dirt or land.. they only buy when they can go vertical GENERALLY speaking as I say this they have just gone into contract of a few parcels next to one I am in process of developing 160 lots on.. but basically that's how it works.

Cost segregation fees are for professional service and are fully tax deductible, so the true cost of the study will be lowered depending on your marginal tax rate.