There is no straight answer without doing a property CMA on the unit. Depends on many factors: condition, days on market, sales in the building and surrounding streets, etc. Understand that a property can be listed for $450K and be over priced significantly or be priced under value but the only way to determine that is through a good valuation using sold data.
Here are some general stat's for all Somerville condo's that have sold in the last 6 months:
Condominium Listings: 305
Avg. Liv.Area SqFt: 1,179.35
Avg. List$: $412,079
Avg. List$/SqFt: $362
Avg. DOM: 59.67
Avg. Sale$: $408,473
Avg. Sale$/SqFt: $359
Get yourself an exclusive buyers agent (NOT the agent who is listing the property) and they will guide you through the entire process including value.
More stat's where the above came from:
Massachusetts Premier Buyer Brokerage
Everything for sale in Somerville: