To buy or not to buy..uc tenant

Viewing a prop next week. Currently has a uc tenant with child (believe the child has health issues). Paying under local rent amount in view of recent rises. The HB for our area is £35 under the rent which she pays herself I assume. I believe she has lived there 2 yrs and presumably wants to stay. So what do i need to do to ensure if we buy and she stays im not setting myself up for a fall. I also believe she has a guarantor. If i did to buy and requested vacant possession but intended to rent it out would this be considered as discrimination?

No it would not. You can insist on vacant possession, but you may have to wait a long time.

Have a look at these 2 web-pages:

And