off: 1st trip to uk, advice please?

[SKARSOL]

hello. my wife karyn and i will be travelling to london for the four
shows there,and we've only booked lodgings for the first night,in the
marble arch area,at $120 u.s.
    this is causing myself some small anxiety,but we thought it possible
that we may be able to find a more economically sound lodging once
there.
    is this a bad idea?any suggestions?please help, as the Rx next door
is nearly out of rolaids.... rj