[coolhanded]

With 4 limpers in front of you, I'm OK with the PF call. Raising isn't going to cut the field down to less than 4 + you, IMO.

I raise preflop here to ensure heads-up. If he calls and still leads turn, I would call, saving 0.5 BB to this point vs. what you did (1 BB flop + 1 BB turn vs. 0.5 BB flop + 2 BB turn) and getting to see the river card. If he calls flop raise and check-raises turn, calling turn is debatable but I probably do it given pot size (8 BB in this case) and because you have some river outs (paired board or a T), though dirty at best. Based on his turn play, I put him on Aces up (A4s or A6s).

Based on what you did, I probably call and see river based on pot size, hoping for a T or paired board. Fold to river bet unimproved.