Offered more than buy it now price

[t3ch4u]

I am new to selling, and I have an item set up as Buy It Now, but the buyer offered a price that was $150 over what the original Buy It Now price is.

They asked that I ship only via UPS since with USPS and FedEx they get their packages stolen from their neighborhood.

It says I'd ship to Houston, TX, but I am suspicious, who offers way more than the original price? Should I just ask them why they would offer so much?

Any advice would help. Thanks!