Looks like Travel Lodge is cheaper than the Premier Inn still. I might come down sat after I go round Croft.

Premier Inn Northampton West (Harpole)
Fri 11 May 12 £33.00 £43.00
Sat 12 May 12 £34.00 £48.00
Sun 13 May 12 £39.00 £48.00
Total 3 nights 1 room £106.00 £139.00

Northampton Upton Way Travelodge
from £32.50 per room per night (Saver rate
(Non-refundable)
Total 3 nights 1 room £97.50