Should I price the land 2 times above market value and offer a low interest rateORPrice the land at current market and use a very high rate?

This is a self directed RRSP or TFSA account that allows you to lend your money out to people with the backing of their mortgage for a high interest rate. 1st, 2nd, 3rd mortgages, down payments, refinances, flipping or renovation money.

I'm in New York but the prices (at least downstate) are much too high for me to make my first deal so looking more upstate and out of state. 

It should be pretty accurate - high level data sites are not always going to be perfect, but should always be directionally correct and AirDNA has a pretty strong track record. 

If you want to quote out high efficiency boilers for six Tripple deckers for example requiring installation of separate gas, meters etc. etc. - that might be a situation where you would want to work with a contractor directly because you would have lots of different options with widely varying costs.

I agree that pricing a rental too high is a classic mistake than can make it sit, but don't you think encouraging landlords to rent quick will make them compromise on the vetting of the tenants?

The barrier to entry seems high, and the price-to-rent ratio isn't very favorable.

But if this is purely an investment, the high maintenance fee is a major concern.Now, let’s look at what happens in the next 5 years:Refinance After 5 Years: Assuming 4% appreciation, your property value will increase to $1,216,653.

There are numerous threads about sub to and many investors believe it is a high risk strategy (especially for seller) and believe buyers who use it “take advantage” of naive sellers.  

The rates are high right now but these loans are limited based on cashflow so you cant take a loan that costs more than you're receiving in rental income.