the MD tax can be quite high...around $3K for my 42 unless you can PROVE that you paid tax elsewhere, then it drops to a couple a grand yearly after that. Finding an affordable liveaboard marina that is commuting distance to your job (unless your job is in SoMd) can be the biggest challenge. YOu may do better trying to find liveaboard and tax friendly slips in VA, again the commute may take a toll.
Re: the tags and license...look in to getting them changed over too, MD does not like those arrangements, they have been known to cruise through apt complexes and taking tag numbers...
BEst of luck, at least you have a job.