I never thought about it. It there an advantage to combining them?
I don't know. If as sometimes is the case and as mentioned, you can't build a garage on a lot without a house, then yes. Do you want to be able to sell lot separately in future? I get sense of small rural town, possibly shrinking like so many, and lots not too much in demand.
I also could believe two 1 acre lots appraise for more than one 2 acre lot. I don't know how to find that out.
Whatever your authority is (AHJ) to allow permitting for construction of a single family dwelling, is where to turn for information on your prospective 'temporary building.'
In Florida, you need to have a unity of title to combine contiguous lots/parcels. One of the things a good real estate attorney would be able to tell you, is at the time the question is posed, and opinion rendered,
are property taxes less for a pair of lots, compared to two single lots/parcels, with a contiguous lot line? Your local taxing authority should be able to answer that question too. In Florida, you can ask for a
zoning determination letter which serves as a statement of fact on questions such as this/these, from the AHJ.
Assuming that the lots are comparable in size and features (waterfront, fronting a high-volume traffic roadway) the assessment for one should be the same for the other. If the lots are two separate zoning districts, like one on a major arterial roadway, the other directly behind it, and sharing a contiguous lot line, they may be valued differently. Also, because of the difference in zoning classifications, to be able to combine the two lots, you would need to seek a change in zoning, to be allowed to combine the two parcels. That would need to be done before the two parcels could be joined.
Something to consider in joining contiguous parcels, assuming that you aren't dealing with different zonings as stated above, is to inquire about the possible future separation of the parcels. Any development you do on the second, open parcel with no permanent structures/improvements, should be done with the possibility of future separation being an easy reversal of your properties being combined. If the AHJ says, "no if you combine the two parcels, you lose development rights to what is now a vacant property, for construction of a single family dwelling," you would need to think long and hard about this. In a way, you probably
do lose development rights to a second SFR, as your land development code probably
does not allow two SFR's on a single parcel. Again, a question for the AHJ. And, get it in writing (the
zoning determination letter, referenced previously).
One reason here in Florida to join two separately approved/legal plots of record, which have a contiguous lot line, if you're using one parcel/lot as your residence of record (and a dwelling on it), there is a homesteading ordinance limiting your increases in property taxes each year. However, if the second undeveloped plot is
not under the legal description of the homesteaded parcel, you could find your property taxes being hiked significantly over time. I've seen it happen, where the undeveloped parcel's property taxes over time rose to being
more-than the property taxes of the parcel with the homestead! This could have been easily avoided by the action of a unity of title.
However, if you remove the accessory structure to restore the second parcel's unimproved status, barring any changes in the land development code, you should be able to request a separation of parcels, which would restore the now again undeveloped parcel's development rights. This is assuming that it is a legal plot of record, with development rights. If it was a legal, non-conforming lot, (a common occurrence) with development rights, prior to your unity of title, the AHJ may have included in your unity of title that any future partition will not restore development rights specifically for a SFR. These are all things you need to consider.
As mentioned by another GJ member, accessory uses by themselves are usually not permitted on a residentially-zoned parcel without a SFR.
I am not an attorney. I worked in Florida as a licensed plans examiner, a lifesafety code inspector, and a staff member doing planning and zoning in local government.
