Adding a little bit of color commentary here (I sold BCC through FEI, the authors of this post):

If you have N products, and ever want to sell any of them, thoroughly decouple the businesses from each other as early as possible. I spent weeks getting BCC moved off of my other business' e.g. CDN accounts, Rackspace account (required a server rebuild), MailChimp account (required an email provider migration of a different project), etc. You don't want to be doing this while you're doing either due diligence or handover -- it introduces technical risk into a project which doesn't tolerate technical risk well.

I'm not one to worry overmuch about costs in the day-to-day operation of my businesses, but several months before selling you want to take a quick look at recurring expenditures and do a purge of any which aren't providing essential business value. Four random SaaS expenditures totaling $200 a month disappear into rounding error of a small SaaS business... but that's ~$10k chewed off the sales price. You want to do this months before the sale to allow time for the numbers to be reflected on your P&L statement and to justify, if asked, "Yep, that isn't actually needed to successfully operate the business."

A surprising thing for me: the market expectation at these valuations is for all-cash or almost-all-cash deals, rather than e.g. significant amounts of seller financing (seller loans buyer money to buy business, collects it and interest over time) or earn-outs (additional payments are due 6~24 months later contingent on the business' performance post-acquisition). If your SaaS is worth e.g. $400k, the expectation in the market is $400k cash or possibly ~$50k or so of financing/earnout and $350k cash. I naively assumed $100k cash and $300k financing would be a common term; it appears this is not the case.

Speculative expenditures in growth which you're not capable of utilizing for e.g. owner bandwidth reasons are a really, really bad idea to buy in e.g. the last year, particularly if those expenditures are recurring. For example, if you're at 50% capacity on your present hosting solution, and you're not growing at 2X a year, I'd encourage a seller to think "Document your understanding of capacity planning and put it in the kit for the new buyer" rather than "Move to a +$1k more expensive hosting solution and solve the scaling problem for the next N years"; that marginal $1k in expenses costs you $40k~$50k out of pocket.

Several of my buddies in solopreneur SaaSland have sold businesses in the last year or so. A common thread among many of the sales is waiting too long to sell. Particularly for those of us with portfolio businesses, an earlier business which was performing decently but not growing w/o manager attention often ended up doing the slow decline into that good night thing for 2+ years prior to finally selling it. This costs both the decline in value of the asset and, additionally, 2+ years of drag on your ability to give all your business cycles to businesses which are working well. (I think substantially all of my similarly situated friends with portfolio businesses would agree that by the time there were four things in the portfolio it was clear one was a great recipient of marginal focus and one was not. Substantially everybody held onto the "not" business longer than they would recommend themselves to have done so in hindsight.)