It was becoming obvious that I just wasn't getting anywhere fast on the house because it lacked a firm foundation. So I finally conquered the reluctance to use the table saw my sister and I bought for this very purpose and put on my carpenter hat.
We use v-g pine boards for the top of the base, which you can make out at the right of the above photo. There was a very good reason.... it mostly escapes me. I think it had to do with cost - narrow cut pine cladding is cheaper than a whole pine board and it's easier (for us) to cut it into strips and then liquid nail it together along the v-g until we have a piece wide enough. We are currently jigsaw challenged, cutting straight lines with those things is an acquired skill .... or you're just born with it.
I used 10mm x 20mm dar for the framework, then added a decorative moulding for bling :) When time came to put the top on it fit like a glove, I was stunned and thrilled!
We could use MDF, which is cheaper again and comes in boards, but again the jigsaw challenge, not to mention there's just something nice about actual wood as opposed to fibreboard.. This project let me add using a table saw, and learning how to countersink screws to my skill set. Getting the house finished is looking less daunting.