Travelling from england to veliko tarnova by car

I used booking.com and used pet friendly hotels   
Travelled with 2 dogs no problems.
Stopped in Germany first night
Hungary second night
Romania third night all hotels were very good and Hungary and Romania very cheap.
I used google maps to plan the route and allowed for 10 hours driving per day because I was travelling alone.
Important to note that your dogs will need their pet passport and if you are travelling through Serbia you will need a international driving licence.
Prior to travelling heard a lot of bad things about Serbia and in particular their police but I had no issues but did not stop overnight.