@Andy,
adverse possession requires a long timeframe in most every jurisdiction, though it varies.
Not exact matches
The statutory period
required for
adverse possession is usually quite long — a decade or two needs to pass before
adverse possession occurs.
The Chief Justice also adopts Justice Cromwell's positioning of the standard of occupation, from the common law perspective, as lying between the minimal occupation which would permit a person to sue a wrongdoer in trespass and the most onerous standard
required to ground title by
adverse possession as against a true owner (para 40).
Adverse possession cases in Massachusetts are factual intensive and
require a substantial amount of historical research and preparation prior to trial.
(1) The line must be certain, well defined, and in some fashion physically designated upon the ground, e.g., by monuments, roadways, fence lines, etc.; (2) in the absence of an express agreement establishing the designated line as the boundary line, the adjoining landowners, or their predecessors in interest, must have in good faith manifested, by their acts, occupancy, and improvements with respect to their respective properties, a mutual recognition and acceptance of the designated line as the true boundary line; and (3) the requisite mutual recognition an acquiescence in the line must have continued for that period of time
required to secure property by
adverse possession.
Many states, although I'm not sure if it is a minority or majority rule, expressly limit
adverse possession, at least, to cases in which the person currently in
possession of the property has acted in good faith at all times, and at least some
require that showing as to everyone in the chain of title relied upon to establish
adverse possession.
As for your parcel under a structure I would think a survey would be
required and then see the rules on
adverse possession in your locale, because that is what someone might claim against your potential claim.