Why do you want to put the house in your sole name? This does not make financial sense, unless it is to do with the divorce proceedings.
It will be expensive to transfer her share of the house over to her later, unless she is your wife by then. There would be stamp duty and gift tax implications if you are not married.
I am assuming you are a first time buyer. If she has owned a house before, you will probably not be regarded as first-time buyers for stamp duty purposes. However, if the only house she owned was with her ex-husband, she will be regarded as a first-time buyer.
If the divorce is causing the problems, then you should wait until that is resolved until you buy your house. I would say that the risk of a rise in prices is balanced by the risk of a fall in prices.
Brendan