This is a rank and rent/lead gen type of domain. Looks like you regged it 4 days ago but was dropped by a plumber or a lead gen company who owned if for a few years without developing it beyond putting up a template. It's indexed, but I doubt it's ranking due to this. Therefore, no local targeted traffic is my guess.
How much it is worth depends on the local plumbing market in Baltimore It's almost impossible to appraise a local lead gen domain without specific local data.
KWfinder.com reports that the keywords phrase "plumbers Baltimore" only had 50 searches in the last 12 mos but CPC for ads is $49/click

. "plumber Baltimore" has 716 searching in 12 mos and CPC is $51/click


Tough city to be in plumbing, eh?
From what I have been able to gather from a little research, it's possible home advisor charges anywhere from $20-70 per lead depending on locality and job type, residential or commercial. AND THESE ARE NON-EXCLUSIVE LEADS!!!
The plural = less value for this domain without a doubt.
IMHO, your max sale price will be to a lead gen/rank and rent company because local businesses don't have the time rank a site and local SEO "experts' have jaded them.
Low to Mid XXX to a lead gen company due to plural and presumably no traffic. Hard to say with local domains like this, though.
I say put it up for sale on afternic or sedo for $500 and see what happens. If it doesn't sell after a few months, go to google and search plumbers baltimore or plumber baltimore and start outbound sales to plumbers on page 2 and 3 or results. Gonna be a tough sale, though. You may want to consider putting up a 10 page site with good on-page SEO and see where that gets you in the results. Might make selling easier.