I've Googled around, any recommendations for bike hire, it appears cheaper to hire a car for a week than hire two bikes for a week ?

There is bike hire next to the harbour (on the harbour entance between the roundabout and the harbour) and another newer place up by the church and plaza.

I have not used either, but I have spoken to them and they were pretty friendly.

yes bike hire is expensive, i think it can be about 50 euro's a day for a family of 4. i bought my bike secondhand from Papagayo bikes in the village near the church. Cost me 70 euro's! very friendly manager Dany, they kit you out as well. Remember it can be very hot, rode this morning for an hour, before 10 am it was 25 degrees.