Can my Self Loan be consolidated?

I use a company called firstmark services and they are horrible. I have 4 loans of 1800.00 through them. And I really would like to consolidate it into one big one of 7200.00 I hate having to make 4 payments and mess with there horrible system. They recently have changed there system a little to accommodate a little, but its still a hle and i am not impressed with there misleading billing. Please help!