Keeping tenants for a short term?

We have bought a property that we are going live in. However we do not want to move into the property until early July at the earliest. We already have a long settlement until the 21st June. There are tenants in the property at the moment.
My questions is this....Would there be any negative implications if we allowed the tenants to stay for a few weeks after settlement??

It will all depend on the tenants. Either they will be okay and no problems of they may decide to stay longer. No lease in place then means no LLI if they decide not to pay rent etc. It all boils down to the type of tenant and relationship you have with that tenant. Was recently asked if a tenant could stay for 2 months after lease expired whilst waiting for another place to be vacant. This tenant received a no because in the past has been a nit picky tenant who complained at the drop of a hat.
I would expect that it would mean you would have to pay CGT when you sell. That could be very expensive. I'd speak to an accountant though.
If you buy the property with existing tenancies (ie NOT vacant possession) you have to give 60 days notice WHEN you own the property.

So you can't have them there for JUST a month after you own it (ie settlement).
Really?? I didn't know that! So is it 60 days from the settlement date or can we give them notice once it goes unconditional?

And what about the vacancy inspections, bond retrieval etc., will the real estate agent do that on our behalf, since it will then be our property when they vacate?

Yes when you are selling you only need to give 30 days but from my understanding the current owner needs to give the notice. As you don't own it you have no power over the tenants. That's my understanding anyway.

I wanted to increase the rent with the existing tenants and was told I couldn't give them notification UNTIL I owned it (ie settlement).