I have purchased two rental properties before. Both were foreclosures. Both had the financing fall through at the last minute. Luckily they were on the cheap side, and I was able to come up with 100% cash to get the deal done, and get a mortgage after completion, but it was quite stressful. So, my advise would be to make sure your financing is rock solid before removing subjects.
The problem with foreclosures is that subjects must be removed prior to setting a court date. So, you would need an inspection, appraisal, etc. before getting a court date, and from my understanding, your offer in court has to be subject free.
On your day in court you may not even get the property, as I was previously outbid, and I have also previously outbid someone else in court. So, your hard earned money on an appraisal may go to waste if you aren't the highest bidder in court.