I know in Denver its ranging $200+/sf here. 

I've seen property in the area sell at 200$/sq. foot but that's top of the range on a very well done property in a healthy market.

I've seen 1800/mo for new build houses in the 250k range.

I don’t know if I should use leverage or cash and what price range I should target for my first rental, then what would be the suggested basic strategy moving forward for a goal never having to get another 9 to 5er.Thank you and look forward to learning,

My plan is to buy a place in the range of $200-280K with a walkout basement so I can rent it while we are living upstairs.

Since initial build, the zoning has since changed to high density residential which does not allow manufactured home parks.

Homes in the neighborhood range from 500 -1.25 mil.

If you need rehab and a stabilization period, you may see rates creep up into the mid 5% range. 

They are the manufacturer, are very large locally (they have 70 to 80 dedicated installation crews).

I would probably stick with growing your portfolio with mid-range cash flowing rentals (focus on low maintenance properties), or scale up into multifamily units (if the numbers make sense).