A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 100,413
Rental cars can be very cheap at BDL. My preferred route to New Haven is to fly to BDL and rent a vehicle and then return it to BDL before flying out from there. It's relatively inexpensive and very convenient, typically with little traffic on good roads if you can avoid crossing through Hartford during rush hour.
Start by checking how much more it would cost to rent a vehicle from one of the majors at BDL and drop it off in New Haven or somewhere else with train convenient transportation. If you're creative and don't mind a bit of a hassle, you might find that a drop off at some place like EWR could be surprisingly cheap for your travel dates.
BTW, if this is near Yale graduation time, plan in advance and expect everything to be expensive and full.