Legal Question in Real Estate Law in California

Re: encroachment

More likely no than yes. The transfer of small strips of urban real property by adverse possession is greatly inhibited by the requirement that the claimant (you) have paid the property taxes for five years. Since property taxes are assessed, and hence paid, based upon legal (deed) descriptions rather than an assessor's noting the location of fences, it is usually impossible to prove payment of taxes. Thus the adverse possession claim fails.

I know of one exception, where an adverse possession claimant was able to get convincing testimony from a county assessor employee who admitted to fixing the taxable value of an urban parcel by personal inspection of a property. There had been prior disputes about the taxes, so a field inspection was done. I think this was very unusual, but I have no expert knowledge of how assessments and appraisals are usually done. My hunch is that office rather than eyeball appraisals are the norm.