Unless your white goods are new or something special, it's probably not worth the cost of transporting them over. Most likely, it probably won't cost a massive amount more to buy new in Bulgaria. You can check costs of these in Bg on sites like emag.bg or technopolis.
We looked at moving costs and decided that when the time comes it will be best for us to buy a used van and move ourselves, so we'll only take personal and special items. General household stuff can be bought there easily enough. The issue is that most furniture needed might have to be bought new. There aren't a lot of second hand shops, and the online sites where people can sell used stuff aren't easy to use without better Bulgarian than we have at present.
But I strongly suggest that you take a quick trip to Bulgaria and see the house first before making moving plans to move everything over, especially with winter coming. It can be very cold and I'm told this winter will be colder than usual. Of course, maybe there's a secure outbuilding or somewhere you can store things on the property. Or Bulgaria Direct have assured you it's been renovated and is absolutely move-in ready with no work needed. Or maybe you're a hardy type who doesn't mind roughing it while doing up a property. In that case, go for it!
I don't know which house you're buying, but it's likely that most properties on the pay-monthly market will need some work doing to be fully liveable. If it's that pretty blue and white cottage on ebay for 16,000, believe them when they state in the listing that it needs renovation work. It's a lovely little house and if I hadn't already bought my house, it would tempt me! In the current market and with the pay monthly option, it's a very fair price. But look closely at all the photos and there are hints of what work might need doing, like the old wooden windows and ancient electrics. Also think what rooms we normally consider necessary in a house don't have photos in the listing and what you're not seeing in the photos that are there.
I love my village house, but I do wish I'd been better prepared for just how much work it needed -- I got something of a shock when I arrived! This is almost certainly true of anyone buying a Bulgarian village house without having seen it first, especially an unrenovated village house. I'd stayed in village houses several times, but renovated ones, and hadn't realised how much work had been needed to get them to that stage.
Maybe you're already aware of all this and have visited Bulgaria multiple times and know just what to expect, in which case, forgive me!