Ltd Company Mortgage application - Personal Guarantee

Property Investment

I am in the process of applying for a 50% mortgage for a buy to let property that I am purchasing through a limited company. After receiving all the survey reports, endless proofs of finances etc and as the solicitors are working towards exchange, the mortgage company has now asked my husband and I (the sole directors in the limited company) to provide personal guarantees to support our mortgage application. Our solicitors advise that this would not be included within their conveyancing quote and have quoted £750 to do this additional work. While I can shop around on the fee, I wonder if, given that no mention was previously made of this requirement in the mortgage paperwork of elsewhere, if this is something that is quite normal that lots of other people have experienced or whether the mortgage company is going beyond what might be considered reasonable.... What do people think?