A two month search for funding seems to be a reasonable time frame. The increase of the cost of submitting a proposal also seems like a good method to keep spammy type proposals off the system and to reduce clutter.

Most business operate in a quarterly fashion, if an update post of the progress being made is not completed in a timely fashion, then on all subsequent proposals from then that should be appended somewhere to let the voter know that this particular team did not keep the voters updated with standard progress reports.