I think that boat may have sailed. HMRC and letting regs have probably killed the market for new entrants. I've owned several BTLs and would certainly not re-enter the market now. And not with £100k which would require additional lending to buy anything half decent that would attract decent tenants (which are the only sort to have).
Try posting on this forum - MSE The House Buying, Renting & Selling Board , there are a lot of knowledgable people there.