removing one party from a mortgage

last october 4 of us bought a house, after living in it for 1 month one of us moved out. now we are trying to buy out this party and get her off the mortgage. she paid £2000 deposit and has contributed £800 in the last year for the mortgage.(our mortgage is £500 per month and we havent recieved any money for 6 months) the house has decreased in value. she wants £6000 to 'buy her out'. what is she legally entitled to?

Normally you would have agreed some split of profit etc. in advance.

It might be a solution to give them one quarter of any appreciation since the purchase, if any. If a decrease in value has occurred they get nothing.

If two or more owners cannot agree on what to do with a piece of property they may petition the court and the court will order a sale or refinancing etc. so that the one or more may get out of the property obligation and/or the other(s) may keep it etc.--it is often done-- (This is true in some cases even for equitable owners that have paid various amounts etc., but for various reasons, may not be on title.) You could threaten to take this action if need be. It may cause compromise which is of course what you need here now.