Tax implications of selling quickly?

[Eric Mcginn]

I know ultimately I need to ask my accountant but he’s busy and expensive to ask preliminary questions. 
I won some land at a county tax auction. My agent has done some research and determined that I’m able to sell it as soon as they mail me the deed and there’s no holding period. 
I would love to improve / build on the land but it’s just not in the schedule for the next few years so I’m thinking it’s best to sell it. Afterall I purchased it as an investment. 

But someone told me that capital gains taxes on a one year investment would be terrible. Any truth to that? 

If I sold it and bought another vacant land property that would be more useful to me to hold, would I then be able to defer those taxes? 

Details:

San Bernardino County California

Bought 10acres for $14k

Looking at asking $40k-50k 

I’d like to buy a small parcel with lake rights in Lake Arrowhead for ~$30k so we can use the private lake. 

Thank you for any guidance in navigating this. I've only done BRRR strategy so I've never sold real estate before.