Putnam Park (Greenwich CT Real Estate) offers some great condos/co-ops within walking distance to downtown Greenwich/Greenwich Avenue/Greenwich Train Station.
Located just a couple blocks to the northeast of Greenwich avenue (entrances on East Putnam & Milbank Ave), Putnam Park offers an affordable condo lifestyle in very well maintained brick construction. This private community is a quiet retreat from the busy streets of downtown Greenwich, while offering an opportunity to live in Greenwich under $400k in many cases.
Here's a quick search of current Putnam Park listings - http://www.greenwichct.com/greenwich-neighborhoods/putnam-park/