As one, a couple states above you, I'll tell you that I built all my rentals and it was the best thing I ever did, course I have a GC's lic (required in NC to use for public use). I built at 60 cents, refi'd at 100 cents and pulled out out 20 cents worth at refi! The party is over in my area because of lot prices. I was lucky enough to get in during the five year window between 2000-2005 when rates came down, values were starting to come up, rentals (new) were few and far between and materials and labor was cheap. Now................lots are expensive, rents stayed the same, labor and materials are back down (as are rates) but the lots values kill it for me, no money left in it to pull out.
If you can build a little 1200 sqft box for under 100K (with lot), pocket a good 20K+ on refi and rent with cash flow...............do it! If not, then you'll need to decide what you ultimate outcome is. I wanted cashflow (primary income for me for a time), equity in the form of "pay" for being on the job 4 months and equity left over for future leverage............all of which I ended up with.
GL with whatever you decide to do.