You say that you cold called your way into a lot that you could make 10-15k. With a home price point in that neighborhood of 225k (yep, price just went up since you posted 2 hours ago lol). If this is true, you can get about 35-45k for that lot. If you’re still in the profit with that number, I would flip the lot to the builder down the street, and start cold calling on more property.
Find a handful of builder that you can flip easily dividable property to (road frontage). Talk to a civil engineer about how many lots that you can divide without getting into major subdivision standards.
Keep flipping land. I’m not trying to be negative Nancy, but If you don’t have the experience in building right now, building a spec will eat your lunch. The reason I say this...
Building a house as a GC is not hard at all once you have the process (I hired someone 3.5 months ago that didn’t know anything, and he’s currently running 10 houses that are on schedule, and homeowners are singing his praises).. The hard part is getting, and keeping a list of great subcontractors that will get you on budget (but you need to know what budget you’re shooting for to sell 1400-1500sf for 225k. Believe me, I know this price point is a tight budget, because that sounds very similar to our S Carolina market).
When we started this building company, it took 6-8 months to line up a list of solid subs that would get us on budget. I knew what we were looking for because I have many friends that build, and used to build houses before the housing crash. But with no experience, I would expect you to break even on your lot, and house for the first few specs.
So, back to flipping land. A builder needs to spend 15-20% of the sale price of the new home on a building lot. If it’s steep, less (10-15%). If it’s a clear, flat field, more (20-25%). If you can keep some small builders (up to 25 houses per year) fed with lots that meet this criteria, then you can do well. I just bought a 6 lot road frontage piece where the wholesaler made 80k on the flip. I overpaid a bit on that one because we were running out of lots, but that’s not a bad deal for my friend, the wholesaler... sounds like you have that skill, and possibly the time to cold call on land?