We live in a wonderful small town that is quickly developing by rich out-of-towners.  They purchase water front / water access lots and build houses for weekend camps.  The houses are mostly basic vinyl siding or hardi plank, and are up on pilings.  We own our home and its 1400 sf 3b/2b. We estimate the value of the house itself to be around $70,000 (we have not had it appraised).  Comps on these lots sell for about $350-450k.  We would be looking at quite an investment however with the purchase of the land, possibly installing a bulk head, sewer, power, cement, pilings, deck, and a few improvements like fixing sheetrock, adding shutters, etc.

So in summary, we are considering moving our current home to a higher value piece of land and then selling.  Hopes are to use the profit to rebuild a slightly larger house to fit our growing family.  I guess my questions is, what type of investment is this called and how would I go about getting more information on whether or not this is even a good idea or if we should just add on to our existing home.