Saying they had "no choice" but to relocate, Grendel's Den Restaurant co-owners Herbert and Sue E. Kuelzer may move their eatery across Winthrop Street-next to the House of Blues-although the condition of the potential site poses problems for the plan.

Sue Kuelzer said she and her husband worry that Grendel's landlord, Intercontinental Companies, will raise rents, which would force them out of the current location, purchased with a $360,000 mortgage.

Grendels, a 27-year-old establishment that was the subject of a landmark church and state separation Supreme Court decision, has submitted preliminary sketches of proposed renovations to the 200-year-old Winthrop Street house, formerly University office space, which they purchased from Harvard this April.